2nd PUC

You can Download Chapter 11 Dual Nature of Radiation and Matter Questions and Answers, Notes, 2nd PUC Physics Question Bank with Answers, Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.

Karnataka 2nd PUC Physics Question Bank Chapter 11 Dual Nature of Radiation and Matter

2nd PUC Physics Dual Nature of Radiation and Matter NCERT Text Book Questions and Answers

Question 1.
Find the
(a) Maximum frequency, and
(b) Minimum wavelength of X-rays produced by 30 kV electrons.
Answer:
V=30kV = 30×10³ V
(a) The maximum frequency of X-rays produced is given by,

Question 2.
The work function of caesium metal is 2.14 eV. When light of frequency 6 x 10¹⁴Hz is incident on the metal surface, photoemission of electrons occurs. What is the
(a) Maximum kinetic energy of the emitted electrons,
(b) Stopping potential, and
(c) Maximum speed of the emitted photoelectrons?
Answer:
υ=6×10¹⁴Hz
ω =2.14eV = 2.14 x 1.6 x 10^-19J
(a) The maximum kinetic energy of the emitted electrons is given by

Question 3.
The photoelectric cut-off voltage in a certain experiment is 1.5 V. What is the maximum kinetic energy of photoelectrons emitted?
Answer:
Here, V₀ = 1.5 V
Maximum kinetic energy. (K.E.)_max
= eV₀ = 1.6 X 10-¹⁹ X 1.5
= 2.4 x 10-¹⁹ J

Question 4.
Monochromatic light of wavelength 632.8 nm is produced by a helium-neon laser. The power emitted is 9.42 raW.

(a) Find the energy and momentum of each photon in the light beam,

(b) How many photons per second, on average, arrive at a target irradiated by this beam? (Assume the beam to have a uniform cross-section which is less than the target area), and

(c) How fast does a hydrogen atom have to travel in order to have the same momentum as that of the photon?
Answer:
λ= 632.8 nm= 632 x 10^-9m
power, P = 9.42 mW = 9.42 x 10^-3 W
(a) Energy of each photon in the light beam,

Question 5.
The energy flux of sunlight reaching the surface of the earth is 1.388 x 10³ W/m². How many photons (nearly) per square meter are incident on the Earth per second? Assume that the photons in the sunlight have an average wavelength of 550 nm.
Answer:
Energy flux of sunlight reaching the surface of the earth,

Question 6.
In an experiment on photoelectric effect, the slope of the cut-off voltage versus frequency of incident light is found to be 4.12 x 10^-15 V s. Calculate the value of Planck’s constant.
Answer:
Slope = 4.12 x 10^-15Vs
\(\frac {h}{e} \) = 4.12 x 10^-15
h = 4.12 x 10^-15 x 1.6 x 10^-19 = 6.6 x 10^-34Js

Question 7.
A 100W sodium lamp radiates energy uniformly in all directions. The lamp is located at the centre of a large sphere that absorbs all the sodium light which is incident on it. The wavelength of the sodium light is 589 nm.
(a) What is the energy per photon associated with sodium light?
(b) At what rate are the photons delivered to the sphere?
Answer:
Power of the lamp, P = 100 W
λ =589nm=589×10^-9m
(a) Therefore, energy of a photon of sodium lamp light,

Question 8.
The threshold frequency for a certain metal is 3.3 x 10¹⁴ Hz. If light of frequency
8.2 x 10¹⁴ Hz is incident on the metal, predict the cutoff voltage for the photoelectric emission.
Answer:

Question 9.
The work function for a certain metal is 4.2 eV. Will this metal give photoelectric emission for incident radiation of wavelength 330 nm?
Answer:
X, = 330 nm = 330 x 10^-9m
∴ Energy of a photon of incident light,

Since the energy of the photon of incident light is less than the work function for the metal, photoelectric emission will not take place.

Question 10.
Light of frequency 7.21 x 10¹⁴ Hz is incident on a metal surface. Electrons with a maximum speed of 6.0 x 10⁵ m/s are ejected from the surface. What is the threshold frequency for photoemission of electrons?
Answer:

Question 11.
Light of wavelength 488 nm is produced by an argon laser which is used in the photoelectric effect. When light from this spectral line is incident on the emitter, the stopping (cut-off) potential of photoelectrons is 0.38 V. Find the work function of the material from which the emitter is made.
Answer:

Question 12.
Calculate the
(a) Momentum, and
(b) de Broglie wavelength of the electrons accelerated through a potential difference of 56 V.
Answer:
V = 56 V
(a) When an electron is accelerated through a potential difference V, it acquires kinetic energy, which is given by, \(\frac { 1 }{ 2 } \)mV² – eV Therefore, momentum of electron.

Question 13.
What is the
(a) Momentum,
(b) Speed, and
(c) de Broglie wavelength of an electron .with kinetic energy of 120 eV.
Answer:
V = 120eV
(a) When an electron is accelerated through a potential difference V, it acquires kinetic energy which is given by

Question 14.
The wavelength of light from the spectral emission line of sodium is 589 nm. Find the kinetic energy at which
(a) An electron, and
(b) A neutron, would have the same de Broglie wavelength.
Answer:
λ = 589 nm= 589 x 10⁹ m.
The de-Broglie wavelength of a particle having energy E is given by,

Question 15.
What is the de Broglie wavelength of
(a) A  bullet of mass 0.040 kg travelling at the speed of 1.0 km/s,
(b) A ball of mass 0.060 kg moving at a speed of 1.0 m/s, and
(c) A dust particle of mass 1.0 x 10 ⁹ kg drifting with a speed of 2.2 m/s?
Answer:
The de-Broglie wavelength of a particle moving with a velocity V is given by

Question 16.
An electron and a photon each have a wavelength of 1.00 nm. Find
(a) Their momenta,
(b) The energy of the photon, and
(c) The kinetic energy of electron.
Answer:
h = 6.63 × 10^-34 Js
λ= 1 nm= 10^-9 m
(a) The electron and the photon will possess the same momentum, which is given by

Question 17.
(a) For what kinetic energy of a neutron will the associated de Broglie wavelength be 1.40 x 10^-10m?
(b) Also find the de Broglie wavelength of a neutron, in thermal equilibrium with matter, having an average kinetic energy of (3/2) k T at 300 K.
Answer:

Question 18.
Show that the wavelength of electromagnetic radiation is equal to the de Broglie wavelength of its quantum (photon).
Answer:
Consider an electromagnetic radiation of wavelength λ and frequency υ. Then,

But
\(\frac { h\upsilon }{ C } =P………………(2)\quad \)
P = momentum of the electromagnetic radiation. From equations (1) and (2), we have
\(\lambda =\frac { h }{ P } \)
Hence the wavelength of electromagnetic radiation is equal to the de-Broglie wavelength associated with its quantum.

Question 19.
What is the de Broglie wavelength of a nitrogen molecule in air at 300 K? Assume that the molecule is moving with the root- mean square speed of molecules at this temperature. (Atomic mass of nitrogen = 14.0076 u)
Answer:
K= 1.38 x 10^-23Jkg-¹
T = 300 K
Nitrogen is a diatomic gas
∴ Mass of the nitrogen gas molecule,
m= 2 x 14.0076 × 10²⁷amu
= 2 x 14.0076 x 10²⁷ = 4.65 ×10^-26 kg.
The root mean square speed of the nitrogen gas molecule is given by

2nd PUC Physics Dual Nature of Radiation and Matter Additional Exercises

Question 20.
(a) Estimate the speed with which electrons emitted from a heated emitter of an evacuated tube impinge on the collector maintained at a potential difference of 500 V with respect to the  emitter. Ignore the small initial speeds of, the electrons. The specific charge of the electron, i.e., its e/m is given to be 1.76 x 10¹¹ C kg^-1

(b) Use the same formula you employ in (a) to obtain electron speed for a collector potential of 10 MV. Do you see what is wrong? In what way is the formula to be modified?
Answer:
(a) V = 500 V
e/m= 1.76×10¹¹ C kg^-1
Due to the applied potential difference between the emitter and the collector, an emitted electron gains kinetic energy, which is given by

Using the same formula as in (a), the speed of electrons at 10 mV comes out to be greater than the speed of light. Since no material particle can move with the speed of light, the result is clearly wrong.

In fact, equation (1) is valid for kinetic energy of the electron, so long as V/C < < 1. At 10 mV, the electrons attain a speed comparable to the speed of light i.e. become relativistic.

In the relativistic domain:- The mass of the electron having rest mass m₍₎ is

Question 21.
(a) A monoenergetic electron beam with electron speed of 5.20 x 10⁶ m s^-1 is subject to a magnetic field of 1.30 x 10^-4 T normal to the beam velocity. What is the radius of the circle traced by the beam, given e/m for electron equals 1.76 x 10ⁿC kg^-1.

(b) Is the formula you employ in (a) valid for calculating radius of the path of a 20 MeV electron beam? If not, in what way is it modified ?

[Note: Exercises 11.20(b) and 11.21(b) take you to relativistic mechanics which is beyond the scope of this book. They have been inserted here simply to emphasise the point that the formulas you use in part (a) of the exercises are not valid at very high speeds or energies. See answers at the end to know what ‘very high speed or energy’ means.]
Answer:
(a) V = 5.2×10⁶ ms¹
B = 1.3 × 10^-4
e/m=1.76 x 10¹¹Ckg-¹

When a magnetic field is applied normally to the path of electron, the force due to the field makes the electron to move along the circular path. The radius of the circular path is given by,

The 10 MeV electron attain a speed comparable to the speed of light i.e. becomes relativistic. In the relativistic domain, the mass of an electron, having rest mass M₀ is given by

Question 22.
An electron gun with its collector at a potential of 100 V fires out electrons in a spherical bulb containing hydrogen gas at low pressure (~10^-2 mm of Hg). A magnetic field of 2.83 x 10^-4 T curves the path of the electrons in a circular orbit of radius 12.0 cm. (The path can be viewed because the gas ions in the path focus the beam by attracting electrons, and emitting light by electron capture; this method is known as the ‘fine beam tube’ method.) Determine e/m from the data.
Answer:
V = 100 V
B = 2.83 ×10^-4 T
r = 12 cm = 12 x 10^-2 m
Due to the applied potential difference between the emitter and the collector, an emitted electron gains kinetic energy which is given by,

When a magnetic field is applied normal to the path of electron, the force due to the filed makes the electron to move along the circular path. The radius of the circular path is given by,

Question 23.
(a) An X-ray tube produces a continuous spectrum of radiation with its short wavelength end at 0.45 Å. What is the maximum energy of a photon in the radiation?
(b) From your answer to (a), guess what order of accelerating voltage (for electrons) is required in such a tube?
Answer:
λ= 0.45 A = 0.45 x 10^-10 m
h = 6.62×10^-34 Js
C = 3 x 10⁸ms^-1
(a) The maximum energy of the photon is given by,
\(E=\frac { hC }{ \lambda } \)

(b) To produce electrons of energy 25.81 keV, accelerating potential of 25.81 kV i.e. order of 26 kV is required.

Question 24.
In an accelerator experiment on high- energy collisions of electrons with positrons, a certain event is interpreted as annihilation of an electron-positron pair of total energy 10.2 BeV into two γ -rays of equal energy. What is the wavelength ‘ associated with each y-ray? (IBeV – 10⁹ eV)
Answer:

Question 25.
Estimating the following two numbers should be interesting. The first number will tell you why radio engineers do not, need to worry much about photons! The second number tells you why our eye can never ‘count photons’, even in barely detectable light.

(a) The number of photons emitted per second by a Medium wave transmitter of 10 kW power, emitting radiowaves of wavelength 500 m.

(b) The number of photons entering the pupil of our eye per second corresponding to the minimum intensity of white light that we humans can perceive (~10^-10 W m^-2). Take the area of the pupil to be about 0.4 cm2, and the average frequency of white light to be about 6 x 10¹⁴Hz.
Answer:
(a) Power of energy transmitted per second,
E = 10 kW = 10⁴ W = 10⁴ Js^-1
λ = 500 m
Energy of one photon,

(b) Minimum intensity of white light = 10¹⁰ Wm²
Area of the pupil = 0.4cm² = 0.4 x 10⁴ m²
∴ Light energy falling on pupil per second
= 10^-10 x 0.4 x 10^-4= 0.4 x 10^-14W
Frequency of white light, u = 6x 10¹⁴ Hz
∴ Energy of the photon of the white light,
hV= 6.62×10^-34 x 6 x 10¹⁴J
∴ Number of photons entering the pupil of our eye per second

Question 26.
Ultraviolet light of wavelength 2271 A from a 100 W mercury source irradiates a photo-cell made of molybdenum metal. If the stopping potential is -1.3 V, estimate the work function of the metal. How would the photo-cell respond to a high intensity (~ 10^s W m^-2) red light of wavelength 6328 A produced by a He-Ne laser?
Answer:


Since wavelength 6.328 Å produced by He-Ne laser and incident on the photocell is greater than,λ_o the photo cell will not respond.

Question 27.
Monochromatic radiation of wavelength nm ( 1 nm = 10^-9 m) from a neon lamp irradiates photosensitive material made of caesium on tungsten. The stopping voltage is measured to be 0.54 V. The source is replaced by an iron source and its 427.2 nm line irradiates the same photo-cell. Predict the new stopping voltage.
Answer:

Question 28.
A mercury lamp is a convenient source for studying frequency dependence of photoelectric emission, since it gives a number of spectral lines ranging from the UV to the red end of the visible spectrum. In our experiment with rubidium photo­cell, the following lines from a mercury source were used:
λ₁= 3650 Å, λ₂= 4047 A, λ₃= 4358 A, λ₄= 5461 A,λ₅= 6907 A,
The stopping voltages, respectively, were measured to be:
V₀₁ = 1.28 V, F₀₂ = 0.95 V, V_n = 0.74 V, V₀₄ = 0.16 V, F_os = 0 V
Determine the value of Planck’s constant h, the threshold frequency and work function for the material.
[Note: You will notice that to get h from the data, you will need to know e (which you can take to be 1.6 x 10^-19 C). Experiments of this kind on Na, Li, K, etc. were performed by Millikan, who, using his own value of e (from the oil-drop experiment) confirmed Einstein’s photoelectric equation and at the same time gave an independent estimate of the value of h.
Answer:
(a) Let the respective frequencies of the five spectral lines of mercury be υ₁, υ₂, υ₃, υ₄ and υ₅. Then

It represents the equation of straight line, whose slope is hυ₀/e and makes an intercept role on negative V₀ – axis. The plot of graph between V (along x-axis) and V₀ (along y-axis) for the given data for the five spectral lines will be shown as in figure.

Question 29.
The work function for the following metals is given: Na: 2.75 eV; K: 2.30 eV; Mo: 4.17 eV; Ni: 5.15 eV. Which of these metals will not give photoelectric emission for a radiation of wavelength 3300 Å from a He-Cd laser placed 1 m away from the photocell? What happens if the laser is brought nearer and placed 50 cm away?
Answer:
λ. = 3300Å= 3300 ×10^-10m
Energy of a photon of incident light,

Since the work functions of Mo and Ni are greater than the energy of the photon of incident light, photoelectric emission will not occur for these metals.

If the laser is brought nearer, the intensity of incident radiation on the metal will increase. It will increase the photoemission in case of Na and K. However, no photo electric emission will .take place in case of Mo and N.

Question 30.
Light of intensity 10^-5 W m^-2 falls on a sodium photo-cell of surface area 2 cm². Assuming that the top 5 layers of sodium absorb the incident energy, estimate time required for photoelectric emission in the wave-picture of radiation. The work function for the metal is given to be about 2 eV. What is the implication of your answer?
Answer:
Since size of the atom is about 10^-10m, the effective area of an atom may be considered as 10^-20 m².
Area of each layer in sodium = 2cm² = 2 x 10^-4m²
Number of atoms in 5 layers of sodium
\(\frac { 2\times { 10 }^{ -4 }\times 5 }{ { 10 }^{ -20 } } \)
If we assume that sodium has one conduction electron per atom, then number of electrons in the 5 layers of sodium = \({ 10 }^{ 17 }\)
Energy incident per second on the surface of the photocell
= 10^-5 x 2 x 10^-4
= 2×10^-9
Since incident energy is observed by 5 layers of sodium, according to wave picture of radiation, the electrons present in all the 5 layers of sodium will share the incident equally.
∴ Energy received by any one electron in the 5 layers of sodium

Since work function of sodium is 2 eV, an electron will be ejected as soon as it gathers energy equal to 2 eV.
∴ Time required for photoelectric emission
= \(\frac { 2 }{ 1.25\times { 10 }^{ 7 } } \) = 1.6 x 10⁷s ≈ 0.5 year
It is contrary to the observed fact that there is no time lag between the incidence of light and the emission of photoelectrons.

Question 31.
Crystal diffraction experiments can be performed using X-rays, or electrons accelerated through appropriate voltage. Which probe has greater energy? (For quantitative comparison, take the wavelength of the probe equal to 1 A, which is of the order of inter-atomic spacing in the lattice) (m_e=9.11 ×10^-31 kg).
Answer:
For x- ray photon of wavelength of 1Å

Question 32.
(a) Obtain the de Broglie wavelength of a neutron of kinetic energy 150 eV. As you have seen in Exercise 11.31, an electron beam of this energy is suitable for crystal diffraction experiments. Would a neutron beam of the same energy be equally suitable? Explain. (m_n = 1.675 x 10^-27 kg)

(b) Obtain the de Broglie wavelength associated with thermal neutrons at room temperature (27 °C). Hence explain why a fast neutron beam needs to be thermalised with the environment before it can be used for neutron diffraction experiments.
Answer:

Since the interatomic spacing (≈10^-10m) is about
100 times greater than the de=Broglie wavelength of 150 eV neutrons, they are not suitable for crystal diffraction experiments.

(b)T=27+273=300k
Energy of the neutron at temperature, T,

Thus, thermal neutrons have wavelength of the order of interatomic spacing
(≈10^-10m) and therefore they are suitable for diffraction experiments. Fast neutrons will possess wavelength quite small as compared to interatomic spacing. Hence for neutron diffraction experiments, fast neutron beam needs to be thermalised.

Question 33.
An electron microscope uses electrons accelerated by a voltage of 50 kV. Determine the de Broglie wavelength associated with the electrons. If other factors (such as numerical aperture, etc.) are taken to be roughly the same, how does the resolving power of an electron microscope compare with that of an optical microscope which uses yellow light?
Answer:
Here, V = 50 kV
Therefore, energy of electrons,
E = 50keV = 50 x 10³ x 1.6 x 10¹⁹ =80 x 10^-15

The resolving power of a microscope is inversely proportional to the wave length of the radiation used. Since wavelength of the yellow light is 5,990 A i.e. 5.99 x 10^-7 m, it follows that the electron microscope will possess resolving power 10 times as large as that of the optical microscope.

Question 34.
The wavelength of a probe is roughly a measure of the size of a structure that it can probe in some detail. The quark structure of protons and neutrons appears at the minute length-scale of  10^-15m or less. This structure was first probed in early 1970’s using high energy electron beams produced by a linear accelerator at Stanford, USA. Guess what might have been the order of energy of these electron beams. (Rest mass energy of electron = 0.511 MeV.)
Answer:
As the quark structure of protons and neutrons appears a the length-scale of 10^-15m, the electron beam used should be of the wavelength of this order i.e.
λ= 10^-15m
Therefore, momentum of the electron beam,

The electron having momentum of this order possesses speed comparable to the speed of light. Therefore, its energy can be found by using the relativistic formula for die total energy of the electron i.e.

Question 35.
Find the typical de Broglie wavelength associated with a He atom in helium gas at room temperature (27 °C) and 1 atm pressure; and compare it with the mean separation between two atoms under these conditions.
Answer:
Mass of the He-atom,
\(m=\frac { atomic\quad weight\quad of\quad He }{ Avogadro\quad Number } \frac { 4 }{ 6.02\times { 10 }^{ 23 } } \)
= 6.645 × 10^-24 g = .6645 ×10^-27 kg
By proceeding as in solved problem No.2.09,
find the de-Broglie wavelength of the He-atom at 27°C.
It can be obtained that de-Broglie wavelength of the He-atom,
λ= 0.73 x 10^-10 m = 0.73 Å
If V is volume of the gas and dj the mean separation between two atoms in the gas, then V = d³ N,
Where N is Avogadro’s number
From the perfect gas equation

i.e the separation between the two He-atoms in the gas is much larger than the Broglie wavelength of the atom.

Question 36.
Compute the typical de Broglie wavelength of an electron in a metal at 27 °C and compare it with the mean separation between two electrons in a metal which is given to be about 2 x 10^-10 [Note: Exercises 11.35 and 11.36 reveal that while the wave-packets associated with gaseous molecules under ordinary conditions are non-overlapping, the electron wave-packets in a metal strongly overlap with one another. This suggests that whereas molecules in an ordinary gas can be distinguished apart, electrons in a metal cannot be distinguished apart from one another. This indistinguishability has many fundamental implications which you will explore in more advanced Physics courses.]
Answer:
It cap be obtained that de-Broglie wavelength of the electron,
λ – 62.3 x 10^-10 m = 62.3 A
Mean separation between two electrons in the metal,

i.e de-Broglie wavelength of the electron is much larger than the separtation between two electrons in the metal.

Question 37.
Answer the following questions:

(a) Quarks inside protons and neutrons are thought to carry fractional charges [(+2/3)e ; (-1/3)e]. Why do they not show up in Millikan’s oil-drop experiment?
(b) What is so special about the combination e/m? Why do we not simply talk of e and m separately?
(c) Why should gases be insulators at ordinary pressures and start conducting at very low pressures?
(d) Every metal has a definite work function. Why do all photoelectrons not come out with the same energy if incident radiation is monochromatic? Why is there an energy distribution of photoelectrons?
(e) The energy and momentum of an electron are related to the frequency and wavelength of the associated matter wave by the relations:
\(\frac { h }{ \lambda } \)
But while the value of x is physically significant, the value of v (and therefore, the value of the phase speed v X) has no physical significance. Why?
Answer:
(a) Quarks having the fractional charges are thought to be confined within a proton or a neutron only. These quarks are bound by forces, which grow stronger, if they are tried to be pulled apart. Thus, the quarks always remain together. It follows that though fractional v charges exist in nature, the observable charges are always integral multiples of e.

(b) The motion of an electron inside electric and magnetic fields is governed by
eV = \(\frac { 1 }{ 2 } \)-mv² = eV; eE = ma and B eV =\(\frac { m{ v }^{ 2 } }{ r } \) where the symbols have their usual meanings.
In all the three relations, e and m occur separately. Further, the value of a physical variable involved in any of these reations can be found by substituting the value of e/m.

(c) The gases keep on getting ionised due to energetic rays [X-rays, Cosmic rays, etc.,] passing through them.

However, at atmospheric pressure, the positive and negative ions are too close and recombine to form neutral gas atoms. Due to this, the gases behave as insulatiors at ordinary pressure.

At low pressures, the gas ions do not recombine as they are appreciably apart. Due to the presence of free ions, the gases start conducting at low pressures.

(d) Work function of a metal is the minimum energy required to knock out an electron (from the conduction band). Since electrons are present in a continuous band of levels, different electrons require different amounts of energy to get out of the atom. For this reason electrons knocked off by a monochromatic radiation posses different energies.

(e) Whereas energy E (= hv) of a particle is arbitrary to within an additive constant, its momentum p (= h/ λ) is not. So, for the matter wave associated with an electron the wavelength λ is physically significant and its frequency v, is not so likewise, the phase speed v λ, is also not physically significant.

2nd PUC Physics Dual Nature of Radiation and Matter Additional Questions and Answers

Question 1.
An electron and an alpha particle have the same de-broglie wavelength associated with them. How are their kinetic energies related to each other?
Answer:

Question 2.
If the frequency of the incident radiation is equal to the threshold frequency, what will be the value of the stopping potential?
Answer:
From Einstein’s photoelectric equation,
hv = hv₀ + eV₀
v = v₀
hv₀=hv₀ + eV₀
v₀=o
∴ Stopping potential = 0

Question 3.
It is harder to remove a free electron from copper than from sodium. Which metal has greater work function? Which has higher threshed wavelength?
Answer:
As it is harder to remove an electron from copper than sodium, the work function of copper is greater

As threshold wavelength is inversely proportional to the work function, its value will be more for sodium.

Question 4.
An electromagnetic wave of wavelength X is incident on a photosensitive surface of negligible work function. If the phot- electrons emitted from this surface have de-Broglie wavelength λ₁ prove that \(\lambda =\frac { 2mc }{ h } { \lambda }_{ 1 }^{ 2 }\)
Answer:
Since photosensitive surface of negligible work function, K.E of emitted electron = energy of incident photon

Question 5.
Find the momentum of an x-ray photon of wavelength.
Answer:
Let p be the momentum of the x-ray photon of wavelength x, then energy of x-ray photon,

Question 6.
The work function of a substance is 4eV. The longest wavelength of light that can cause photoelectric emission from this substance is approximately
(A) 540 nm
(B) 400 nm
(C) 310 nm
(D) 220 nm
Answer:
(C) 310 nm

Question 7.
The mass of a photon at rest is
(A) zero
(B) 1.67 x 10^-35kg
(C) 1 amu
(D) 9 x 10³¹ kg
Answer:
(A) zero

Question 8.
Which one among the following shows particle nature of light?
(A) Photoelectric effect
(B) Interference
(C) Refraction
(D) Polarisation
Answer:
(A) Photoelectric effect

Question 9.
Planck’s constant has the dimensions of
(A) linear momentum
(B) angular momentum
(C) energy
(D) power
Answer:

Question 10.
The de-Broglie wave corresponding to a particle of mass m and velocity v has a wavelength associated with it
(A) \(\frac { h }{ mv } \)
(B) hmv
(C) \(\frac { mh }{ v } \)
(D) \(\frac { m }{ hv } \)
Answer:

You can Download Chapter 1 Accounting for Partnership : Basic Concepts Questions and Answers, Notes, 2nd PUC Accountancy Question Bank with Answers Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.

Karnataka 2nd PUC Accountancy Question Bank Chapter 1 Accounting for Partnership : Basic Concepts

You can Download Chapter 10 Consumption And Investment Function Questions and Answers, Notes, 2nd PUC Economics Question Bank with Answers Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.

Karnataka 2nd PUC Economics Question Bank Chapter 10 Consumption And Investment Function

2nd PUC Economics Consumption And Investment Function One Mark Questions and Answers

Question 1.
Write the meaning of consumption.
Answer:
Consumption refers to using of goods and services to attain desired satisfaction. It also represents the total quantity of products bought and used by consumers during a particular period of time.

Question 2.
What to do you mean by savings?
Answer:
Savings refer to the excess of income over expenditure.

Question 3.
Define investment.
Answer:
According to J.M.Keynes, investment refers to an addition to the nation’s physical stock of capital goods like roads, bridges, buildings, machines etc.

Question 4.
What is MPC?
Answer:
MPC (Marginal Propensity to Consume) refers to the ratio of change in consumption to the change in income.

where ∆c refers to change in consumption and ∆y refers to change in the income of the consumer.

Question 5.
Give the meaning of Multiplier.
Answer:
Multiplier is the ratio of the total change in income to the initial change in investment. It expresses the quantitative relationship between increase in income and increase in investment.

Question 6.
What is APC?
Answer:
APC – Average Propensity to Consume is the ratio of consumption expenditure to income in a given period of time. APC = C/Y where C is consumption and Y is income.

Question 7.
How do you calculate MPS?
Answer:
The Marginal Propensity to save (MPS) is obtained as follows:
MPS = 1 – MPC.

2nd PUC Economics Consumption And Investment Function Two Marks Questions and Answers

Question 1.
Define Income as per J.M. Keynes.
Answer:
According to J.M.Keynes, Income refers to total money remuneration received by four factors of production in the form of rent, wages, interest and profit. It is expressed as follows:
Y = C + I where, Y is income, C is consumption expenditure and ‘I’ investment expenditure.

Question 2.
How is saving equal to investment?
Answer:
The equality between saving and investment is through the mechanism of rate of interest. If the saving is more than investment, the rate of interest falls, investment increases and savings comes down. When the saving is less than investment, rate of interest increases and investment comes down and the savings gets increased to the level of investment.

According to Keynes, Y = C + S and Y = C + I, therefore C + S = C + I, so S = I
Y-income, C-consumption, S-savings, I-investment.

Question 3.
State the factors which influence Marginal Propensity to Consume(MPC).
Answer:
There are two main factors which affect the Marginal Propensity to Consume viz., Subjective factors and Objective factors. The subjective factors include psychological characters of human beings, social practices and institutions etc. The objective factors include, change in the wage level, changes in fiscal policy, change in expectations, change in rate of interest etc.

Question 4.
Briefly explain the relationship between multiplier and MPC.
Answer:
The effect of multiplier depends on Marginal propensity to consume as its value is determined by MPC alone. If MPC is higher, multiplier will also be higher. The multiplier can be calculated by the following formula:

Question 5.
Differentiate between autonomous and induced investments.
Answer:

Autonomous Investment	Induced Investment
(i) It is independent of the level of income.	(i) It is profit or income motivated.
(ii) It is influenced by innovations, growth of population, social and legal institutions etc.	(ii) It is made by the people as a result of change in income.
(iii) It is income inelastic	(iii) It is income elastic

Question 6.
Mention any four types of investments.
Answer:
The types of investments are as follows:

1. Private Investment and Public Investment.
2. Induced Investment and Autonomous Investment.
3. Ex-ante Investment (Planned) and Ex-post Investment (unplanned).
4. Gross Investment and Net Investment.

2nd PUC Economics Consumption And Investment Function Five Marks Questions and Answers

Question 1.
What is investment? Briefly explain the various types of investment.
Answer:
According to J.M.Keynes, investment refers to an addition to the nation’s physical stock of capital goods like roads, bridges, buildings, machines etc.

The types of investment are as follows:
1. Private Investment and Public Investment: Private investment is that investment which is undertaken by private individuals, enterprises, industrialists etc. Public investments are those investments which are made by Government authorities. The intention of private investment is profit and public investment is social benefits.

2. Induced Investment and Autonomous Investment: Induced investment is made by the people as a result of change in their income level. It is profit or income motivated. So, it is income elastic. The autonomous investment is public investment which is independent of the level of income. It is income inelastic. It is influenced by innovations, growth of population, social and legal institutions etc.

3. Ex-ante Investment and Ex-post Investment: Ex-ante investment is that investment which is actually planned according to objectives and investment is made. This investment is planned in advance. The ex-post investment is that investment which cannot be planned in advance. It is that investment which arises instantly during the course of production process.

4.  Gross Investment and Net Investment: Gross investment is the total value of the asset made or created. It includes buildings, dams, roads, railways, industries, etc. The net investment is obtained by deducting depreciation from Gross Investment.

Question 2.
Explain the J.M.Keynes consumption function in brief.
Answer:
The consumption function also called as propensity to consume refers to income consumption relationship. It is a functional relationship between Total consumption and Gross national income. The consumption function may be represented as follows:
C = f (Y). where C is consumption, Y is income and f is die functional relationship.

In fact, consumption function is a schedule of the various amounts of consumption expenditure corresponding to different levels of income. The following table shows the imaginary consumption schedule:

Income (Y) in crores	Consumption(C) in crores.
0	30
50	60
120	120
180	160
240	200
300	240
360	280

The above table shows that the consumption is an increasing function of income because consumption expenditure increases with increase in income. When the income is zero, people spend out of their past savings on consumption because they must eat to live. When income is 50 crores, it is still not sufficient to meet the consumption expenditure of the community as the consumption expenditure (Rs. 60) is more than the income (Rs. 50).

When the income is equal to 120 crores the consumption is also Rs. 120 crores. After this stage, income is shown to increase by 60 crores (240 – 180) and the consumption goes up by only 40 crores (160 -120). This implies that increase in consumption is less than the corresponding increase in income.

In the above diagram, income is measured horizontally and consumption is measured vertically. 45 degree is the unity line where at all levels income and consumption are equal. The C curve is a linear consumption function based on the assumption that consumption changes by the same amount. Its upward slope to the right indicates that consumption is an increasing function of income.

B is the break-even point where C = Y or OY₁ = OC₁. When income rises to OY₂, consumption also increases to OC₂, but the increase in consumption is less than the increase in income, CC₁ <  Y₁ Y₂. The portion of income not consumed is saved and represented as SS₁.

Question 3.
Explain the investment function of Keynes in brief.
Answer:
Generally, investment means buying shares, stocks, bonds, securities existing in stock market. According to J.M.Keynes, investment refers to real investment which adds to capital stock. It leads to increase in level of income and production by increasing the production and purchase of capital goods.

Investment is the production or acquisition of real capital assets during any period of time. Capital and investment are related to each other through net investment. As the income of the community increases, consumption also increases. But, it does not increase in the same proportion. There will be a gap between income and consumption. The gap must be filled by increasing employment and production. For this, investment is needed.

The decision to invest in a new capital asset depends on whether the expected rate of return on the new investment is equal to or greater or less than the rate of interest to be paid on the funds needed to purchase this asset. It is only when the expected rate of return is higher than the interest rate that investment will be made in acquiring new capital assets.

In reality, there are three factors that are taken into consideration while making any investment decision.
They are as follows:

1. The cost of capital asset.
2. The expected rate of returns during its lifetime.
3. Market rate of interest.

Question 4.
Explain the concept of Multiplier of Keynes.
Answer:
According to Keynes, Multiplier establishes a precise relationship, given the propensity to consume, between aggregate employment and income and the rate of investment. It tells us that, when there is an increment of investment, income will increase by an amount which is K times the increment of investment. It can be expressed as follows:
K = ∆Y/∆I, where ∆Y is the change in income and ∆I is the change in investment and K is the multiplier.

Problem: If the investment increases from Rs.1000 crores to Rs.1500 crores, income may increase from Rs.2000 to Rs.3000 crores, then find the multiplier.

In the multiplier theory, the important element is the multiplier coefficient, K which refers to the power by which any initial investment expenditure is multiplied to obtain a final increase in income. The value of multiplier is determined by the MPC. The higher the rate of MPC, the higher is the value of multiplier and vice versa.

The effect of multiplier depends on Marginal propensity to consume as its value is determined by MPC alone. If MPC is higher, multiplier will also be higher. The multiplier can be calculated by the following formula:
If MPC is deducted from I, we get MPS i.e., Marginal Propensity to Save. Now the above formula becomes as follows:

If MPC is deducted from I, we get MPS i.e., Marginal Propensity to Save. Now the above formula becomes as follows:

Working of Multiplier: Multiplier works both forward and backward. In forward working, an increase in investment leads to increased production which creates income and generates consumption expenditure. This process continues in dwindling series till no further increase in income and expenditure is possible.

In backward operation, the multiplier operates backward. A reduction in investment will lead to contraction of income and consumption which, in turn, will lead to cumulative decline in income and consumption till the contraction in aggregate income is the multiple of the initial decrease in investment.

The size of multiplier varies directly with the size of the MPC. The working of multiplier can be illustrated with the help of the following diagram:

In the above diagram, the original investment is I.I (OI) and the original income is OY. S…S is the saving curve. The two curves intersect at point E. If there is an increase in investment, then the I..I curve will shift to a position above the earlier level to I,…I. Now, curves I,..I, and S..S intersect at point E₁ and the new level of income OY₁ is determined. This emphasizes the fact that an initial increase in investment leads to a large increase in income.

Question 5.
What is Multiplier? What is its importance?
Answer:
According to J.M. Keynes, Multiplier establishes a precise relationship, given the propensity to consume, between aggregate employment and income and the rate of investment. It tells us that, when there is an increment of investment, income will increase by an amount which is K times the increment of investment. It can be expressed as follows:
K = ∆Y/∆I, where ∆Y is change in income and ∆I is Change in investment and K is the multiplier.

The concept of multiplier is an important contribution of Keynes to the theory of income, output and employment.
The importance of multiplier is as follows:

• The theory of multiplier highlights the importance of investment in income and employment theory.
• The multiplier throws a spotlight on the different phases of the business cycles.
• It helps in bringing equality between saving and investment.
• It is an important tool in formulating economic policies.
• It provides guidelines to achieve full employment.
• It highlights the importance of deficit financing (Public expenditure greater than public revenue).
• It points out the role of public investment in economic development.

2nd PUC Economics Consumption And Investment Function Ten Marks Questions and Answers

Question 1.
Explain the concepts of saving and investment. Discuss the equality between saving and investment.
Answer:
The consumption function also called as propensity to consume refers to income consumption relationship. It is functional relationship between Total consumption and Gross national income. The consumption function may be represented as follow.

C = f (Y). where C is consumption, Y is income and f is the functional relationship.

In fact, consumption function is a schedule of the various amounts of consumption expenditure corresponding to different levels of income.

(a) Investment function:
Generally, investment means buying shares, stocks, bonds, securities existing in stock market. According to J.M.Keynes, investment refers to real investment which adds to capital stock It leads to increase in level of income and production by increasing the production and purchase of capital goods.

Investment is the production or acquisition of real capital assets during any period of time. Capital and investment are related to each other through net investment. As the income of the community increases, consumption also increases. But, it does not increase in the same proportion. There will be a gap between income and consumption. This gap must be filled by increasing employment and production. For this, investment is needed.

The decision to invest in a new capital asset depends on whether the expected rate of return on the new investment is equal to or greater or less than the rate of interest to be paid on the funds needed to purchase this asset. It is only when the expected rate of return is higher than the interest rate that investment will be made in acquiring new capital assets.

In reality, there are three factors that are taken into consideration while making any investment decision. They are as follows:

1. The cost of capital asset.
2. The expected rate of returns during its lifetime.
3. Market rate of interest.

(b) Equality between saving and investment:
The equality between saving and investment is through the mechanism of rate of interest. If the saving is more than investment, the rate of interest falls, investment increases and saving comes down. When the saving is less than investment, rate of interest increases and investment comes down and the savings gets increased to the level of investment.

According to Keynes, Y = C + S and Y = C + I, therefore C + S = C + I, so S = I
Y-income, C-consumption, S-saving, I-investment.

Question 2.
Explain Keynes consumption function. Discuss the properties of consumption function.
Answer:
The consumption function also called as propensity to consume refers to income consumption relationship. It is a functional relationship between Total consumption and Gross national income. The consumption function may be represented as follows:
C = f (Y). where C is consumption, Y is income and f is the functional relationship.

In fact, consumption function is a schedule of the various amounts of consumption expenditure corresponding to different levels of income. The following table shows the imaginary consumption schedule:

Income (Y) in crores	Consumption(C) in crores
0	30
50	60
120	120
180	160
240	200
300	240
360	280

The above table shows that the consumption is an increasing function of income because consumption expenditure increases with increase in income. When the income is zero, people spend out of their past savings on consumption because they must eat to live. When income is is 50 crores, it is still not sufficient to meet the consumption expenditure of the community which at 60 crores is more than the income. When the income is equal to 120 crores which is the basic consumption level. After this stage, income is shown to increase by 60 crores and the consumption goes up by only 40 crores. This implies that increase in consumption is less than the corresponding increase in income.

In the above diagram, income is measured horizontally and consumption is measured vertically.. 45 degree is the unity line where at all levels income and consumption are equal. The C curve is a linear consumption function based on the assumption that consumption changes by the same amount. Its upward slope to the right indicates that consumption is an increasing function of income. B is the break-even point where C = Y.

When income rises to OC₂, consumption also increases to OY₂, but the increase in consumption is less than the increase in income, C₁C₂ < Y₁Y₂. The portion of income not consumed is saved and is represented as SS₁.

Question 3.
What do you mean by investment function? Discuss the types and determinants of investment.
Answer:
Generally, investment means buying shares, stocks, bonds, securities existing in stock market. According to J.M.Keynes, investment refers to real investment which adds to capital stock. It leads to increase in level of income and production by increasing the production and purchase of capital goods.

Investment is the production or acquisition of real capital assets during any period of time. Capital and investment are related to each other through net investment. As the income of the community increases, consumption also increases. But, it does not increase in the same proportion. There will be a gap between income and consumption. This gap must be filled by increasing employment and production. For this, investment is needed.

The decision to invest in a new capital asset depends on whether the expected rate of return on the new investment is equal to or greater or less than the rate of interest to be paid on the funds needed to purchase this asset. It is only when the expected rate of return is higher than the interest rate that investment will be made in acquiring new capital assets.

In reality, there are three factors that are taken into consideration while making any investment decision. They are as follows:

1. The cost of capital asset.
2. The expected rate of returns during its lifetime.
3. Market rate of interest.

The types of investment are as follows:
1. Private Investment and Public Investment: Private investment is that investment which is undertaken by private individuals, enterprises, industrialists etc. Public investments are those investments which are made by Government authorities. The intention of private investment is profit and public investment is social benefits.

2. Induced Investment and Autonomous Investment: Induced investment is made by the people as a result of change in their income level. It is profit or income motivated. So, it is income elastic. The autonomous investment is public investment which is independent of the level of income. It is income inelastic. It is influenced by innovations, growth of population, social and legal institutions etc.

3. Ex-ante Investment and Ex-post Investment: Ex-ante investment is that investment which is actually planned according to objectives and investment is made. This investment is planned in advance. The ex-post investment is that investment which cannot be planned in advance. It is that investment which arises instantly during the course of production process.

4. Gross Investment and Net Investment: Gross investment is the total value of the asset made or created. It includes buildings, dams, roads, railways, industries, etc. The net investment is obtained by deducting depreciation from Gross Investment.

Determinants of Investments:
The investment depends on two factors viz., Marginal efficiency of Capital and rate of interest.
a) Marginal Efficiency of Capital (MEC): The MEC is the highest rate of returns expected from an additional unit of a capital asset over its cost. According to Kurihara “ MEC is the ratio between the prospective yield of additional capital goods and their supply price”. The prospective yield is the aggregate net returns from an asset during its lifetime, while the supply price is the cost of producing the asset.

If the supply price of a capital asset is Rs.20;000 and its annual yield is Rs.2,000, the Marginal Efficiency of this asset is 2000/20000 x 100/1 = 10%. The MEC is the percentage of profit expected from a given investment on a capital asset.

b) Rate of Interest: The investment is also determined by the rate of interest. If the rate of interest is higher, the investment will be low as MEC becomes less. If the MEC is higher than the rate of interest, there will be a tendency to borrow funds in order to invest in new capital assets. If the MEC is lower than the rate of interest, no firm will borrow to invest in capital assets. Thus the equilibrium condition for a firm to hold the optimum capital stock is where the MEC is equal to the interest rate.

You can Download Chapter 12 Atoms Questions and Answers, Notes, 2nd PUC Physics Question Bank with Answers, Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.

Karnataka 2nd PUC Physics Question Bank Chapter 12 Atoms

2nd PUC Physics Atoms NCERT Text Book Questions and Answers

Question 1.
Choose the correct alternative from the clues given at the end of each statement:

1. The size of the atom in Thomson’s model is ………….. the atomic size in Rutherford’s model, (much greater than/ no different from/much less than.)
2. In the ground state of …………..electrons are in stable equilibrium, while in electrons always experience a net force. (Thomson’s model/ Rutherford’s model.)
3. A classical atom based on ………….. is doomed to collapse. (Thomson’s model/ Rutherford’s model.)
4. An atom has a nearly continuous mass distribution in a ………….. but has a highly non-uniform mass distribution in (Thomson’s model/ Rutherford’s model.)
5. The positively charged part of the atom possesses most of the mass in ………….. (Rutherford’s model/both the models.)

Answer:

1. No different from
2. Thomson’s model, Rutherford’s model
3. Rutherford’s model
4. Thomson’s model, Rutherford’s model
5. both the models.

Question 2
Suppose you are given a chance to repeat the alpha-particle scattering experiment using a thin sheet of solid hydrogen in place of the gold foil. (Hydrogen is a solid at temperatures below 14 K.) What results do you expect?
Answer:
α-particle is much heavier than hydrogen nuclei. Therefore, α-particles pass through solid hydrogen without deflection. In other words, α-particles are not scattered by solid hydrogen.

Question 3.
What is the shortest wavelength present in the Paschen series of spectral lines?
Answer:
The wavelengths of the spectral lines in the Paschen series are given by

Question 4.
A difference of 2.3 eV separates two energy levels in an atom. What is the frequency of radiation emitted when the atom make a transition from the upper level to the lower level?
Answer:

Question 5.
The ground state energy of the hydrogen atom is -13.6 eV. What are the kinetic and potential energies Of the electron in this state?
Answer:
The kinetic energy of the electron in an orbit is numerically equal to its total energy. Therefore, the kinetic energy of the electron = 13.6 eV
The potential energy of the electron in an orbit is equal to twice, its total energy
= -13.6 ×2
= -27.2 eV.

Question 6.
A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of the photon.
Answer:
The energy of the electron in the ground state
E_e = -13.6 eV
Also, the energy of the electron in n=4 level,

Question 7.
(a) Using Bohr’s model calculates the speed of the electron in a hydrogen atom in the n = 1, 2, and 3 levels,
(b) Calculate the orbital period in each of these levels.
Answer:
(a) The speed of an electron in the n^th orbit of an H-atom is given by

From equation (i), it follows that the velocity of electron in an orbit of a hydrogen atom is inversely proportional to its quantum number (n).

(b) The orbital period of an electron in the n^th orbit of an H-atom is given by

It follows that orbital period of an electron in H-atom is directly proportional to the cube of its quantum number.

Question 8.
The radius of the innermost electron orbit of a hydrogen atom is 5.3 x 10^-11. What are the radii of the n = 2 and n = 3 orbits?
Answer:
The radius of an orbit in a hydrogen atom is directly proportional to the square of its quantum number i.e.

Question 9.
A 12.5 eV electron beam is used to bombard gaseous hydrogen at room temperature. What series of wavelengths will be emitted?
Answer:
The first, second and third excited energies for hydrogen atom are
E’ ₁ = E₂ – E₁ = -3.4 – [-13.6] = 10.2 eV,
E’₂ = E₃ – E₁= -1.51 – [-13.6] = 12.09 eV,
and E’₃ = E₄ – E₁ = -0.85 – [-13.6] = 12.75 eV
It follows that when a 12.5 eV electron beam is used to bombard gaseous hydrogen at room temperature, the H – atoms at the most will be raised to n = 3 level. The H – atoms may come to ground state directly or via n = 2 level. Therefore, the wavelengths emitted will lie in Balmer series [for de-excitation from n = 3 level to n = 2 and 1 level] and Lyman series [for de­excitation from n = 2 level to n = 1 level].

Question 10.
In accordance with the Bohr’s model, find the quantum number that characterises the earth’s revolution around the sun in an orbit of radius  1.5 x 10¹¹ m with orbital speed 3 x 10⁴ m/s. (Mass of earth = 6.0 x 10²⁴)
Answer:
Here, m = 6.0 x 10²⁴ kg; r = 1.5×10ⁿm
and v = 3 x 10⁴ ms^-1
The angular momentum of the earth,
mvr = 6.0×10²⁴ x 3 x 10⁴ x 1.5 x 10¹¹ = 2.7 x 10⁴⁰ kg ms^-1 
In accordance with Bohr’s model

2nd PUC Physics Atoms Additional Exercise

Question 11.
Answer the following questions, which help you understand the difference between Thomson’s model and Rutherford’s model better.

(a) Is the average angle of deflection of α-particles by a thin gold foil predicted by Thomson’s model much less, about the same, or much greater than that predicted by Rutherford’s model?

(b) Is the probability of backward scattering (i.e., scattering of α-particles at angles greater than 90°) predicted by Thomson’s model much less, about the same, or much greater than that predicted by Rutherford’s model?

(c) Keeping other factors fixed, it is found experimentally that for small thickness t, the number of α-particles scattered at moderate angles is proportional to t. What clue does this linear dependence on t provide?

(d) In which model is it completely wrong to ignore multiple scattering for the calculation of average angle of scattering of a -particles by a thin foil?

Answer:
(a) Is the average angle of deflection of α-particles by a thin gold foil predicted by Thomson’s model much less, about the same, or much greater than that predicted by Rutherford’s model?

(b) Is the probability of backward scattering (i.e., scattering of α-particles at angles greater than 90°) predicted by Thomson’s model much less, about the same, or much greater than that predicted by Rutherford’s model?

(c) Keeping other factors fixed, it is found experimentally that for small thickness t, the number of α-particles scattered at moderate angles is proportional to t. What clue does this linear dependence on t provide?

(d) In which model is it completely wrong to ignore multiple scattering for the calculation of the average angle of scattering of a -particles by a thin foil?

Question 12.
The gravitational attraction between electron and proton in a hydrogen atom is weaker than the Coulomb attraction by a factor of about 10^-40. An alternative way of looking at this fact is to estimate the radius of the first Bohr orbit of a hydrogen atom if the electron and proton were bound by gravitational attraction. You will find the answer interesting.
Answer:
Let m and m be the masses of electron and proton respectively. If the electron and proton were bound only by gravitational attraction, then

According to Bohr’s quantization conditions, the angular momentum of the electron.

Question 13.
Obtain an expression for the frequency of radiation emitted when a hydrogen atom de-excites from level n to level (n-1). For large n, show that this frequency equals the classical frequency of revolution of the electron in the orbit.
Answer:
When a hydrogen atom de-excites from level n₁ to n_p the frequency of radiation emitted is given by


Hence, when n is large, the frequency of radiation emitted is equal to the classical frequency of revolution of the electron in the orbit.

Question 14.
Classically, an electron can be in any orbit around the nucleus of an atom. Then what determines the typical atomic size? Why is an atom not, say, a thousand times bigger than its typical size? The question had greatly puzzled Bohr before he arrived at his famous model of the atom that you have learned in the text. To simulate what he might well have done before his discovery, let us play as follows with the basic constants of nature and see if we can get a quantity with the dimensions of length that is roughly equal to the known size of an atom (~ 10^-10m).

(a) Construct a quantity with the dimensions of length from the fundamental constants e, m_e, and c. Determine its numerical value.

(b) You will find that the length obtained in (a) is many orders of magnitude smaller than the atomic dimensions. Further, it involves c. But energies of atoms are mostly in non-relativistic domain where c is not expected to play any role. This is what may have suggested Bohr to discard c and look for ‘something else’ to get the right atomic size. Now, the Planck’s constant h had already made its appearance elsewhere. Bohr’s great insight lay in recognising that h, me, and e will yield the right atomic size. Construct a quantity with the dimension of length from h, m_e, and e and confirm that its numerical value has indeed the correct order of magnitude.
Answer:
(a) The quantity with the dimensions of length constructed from the fundamental constants e, m, and c is

(b) The quantity with the dimensions of length constructed from the fundamental constants h, e, and m is the radius of the innermost orbit (n = 1) of the H – atom. It is given by,

It is also called Bohr’s radius
Substituting the values of h, m_e and 4π∈_o in equation (1),

Question 15.
The total energy of an electron in the first excited state of the hydrogen atom is about -3.4 eV.
(a) What is the kinetic energy of the electron in this state?
(b) What is the potential energy of the electron in this state?
(c) Which of the answers above would change if the choice of the zero of potential energy is changed?
Answer:
We know that K.E and P.E of the electron in the n^th energy state of the hydrogen atom are respectively given by

The first excited state corresponds to n = 2 level.
Now, the total energy of an electron in
n = 2 state is given to be – 3.4 eV.

(a) Therefore, K.E of the electron in the first excited state (n = 2) of the hydrogen atom

(b) E of the electron in the first excited state (n = 2) of the hydrogen atom.

(c) If the zero of potential energy is chosen differently, K.E does not change. The P.E and total energy will change

Question 16.
If Bohr’s quantisation postulate (angular momentum = nh/2π) is a basic law of nature, it should be equally valid for the case of planetary motion also. Why then do we never speak of quantisation of orbits of planets around the sun?
Answer:
The mass of a planet is very large as compared to that of electron and accordingly, its angular momentum is very large. For \(\frac { h }{ 2\pi } \) example, in terms of the angular, from the
Bohr’s quantisation relation,\(\frac { nh }{ 2\pi } \) it follows that for the orbital motion of the earth, n = 10⁷⁰. For such a large value of n, the difference in the energies of the successive energy levels are so small as compared to the energies associated with the energy levels that these levels form an energy continuum, i.e the levels appear to be continuous.

Question  17.
Obtain the first Bohr’s radius and the ground state energy of a muonic hydrogen atom [i.e., an atom in which a negatively charged muon (μ^–) of mass about 207m_e orbits around a proton].
Answer:
Let m be the mass of the electron. the firest Bohr radius of H- atom is given by,

in a muonic hydrogen atom, in place of an electron, a negatively charged muon having mass 207 m. revolves around the nucleus of hydrogen i.e. proton.
If r₁‘ is first Bohr’s radius of muonic hydrogen atom,

2nd PUC Physics Atoms Additional Questions and Answers

Question 1.
What is the ratio of radii of the orbits corresponding to first excited state and ground state of hydrogen atom?
Answer:
The radius of the n^th orbit, r_n α n²
The ground state corresponds to n = 1 and the
a first excited state corresponds to n = 2

Question 2.
The ground state energy of the hydrogen atom is -13.6eV. What are the kinetic and potential energies of the electron in this state?
Answer:
The potential energy (E_p) of the electron in an orbit is equal to twice its total energy (E) = -13.6 x 2 = -27.2eV
The kinetic energy (E_k) of the electron in an orbit is equal to the negative of its total energy (E) = E_k – E = -(-13.6) = 13.6 eV.

Question 3.
The radius of 1st electron orbit of hydrogen atom is 5.3 x 10^-11 m. What is the radius of 2^nd orbit?
Answer:

Question 4.
What is energy possessed by an electron in n = ∞ ?
Answer:
Energy of electron in n^th orbit of a hydrogen atom is given by

Question 5.
If 13.6eV energy is required to ionise the hydrogen atom, then the energy required to remove an electron from n = 2 is
(A) 2 eV
(B) 0 eV
(C) 3.4 eV
(D) 6.8 eV
Answer:
Required energy

Question 6.
The transition from state n = 3 to n = 1 in a hydrogen like atom results in ultraviolet radiation. Infrared radiation will be obtained in transition from
(A) n = 2  to  n = 1
(B) n = 3 to n = 2
(C) n = 4  to n = 2
(D) n = 5 to n = 4
Answer:
Infrared region lies for the Bracket series, i.e. the transition from n = 5 to n = 4.

Question 7.
Which of the following transition in a hydrogen atom emits the photon of highest frequency?
(A) n = 2 to  n = 6
(B) n   = 2 to n =   1
(C) n = 6  to    n = 2
(D) n   = 1 to n =   2
Answer:
\(v={ R }_{ c }\left( \frac { 1 }{ { n }_{ i }^{ 2 } } -\frac { 1 }{ { n }_{ f }^{ 2 } } \right) \)
Substituting various values of n and n_p it is observed, maximum frequency is obtained for transition from n = 2 to n = 1.

Question 8.
When a hydrogen atom is raised from ground to excited state,
(A) The P.E increases and K.E decreases
(B) The P.E decreases and K.E increases
(c) Both P.E and K.E increase
(d) Both P.E and K.E decreases
Answer:
(B) The P.E decreases and K.E increases

Question 9.
In which of these, will radius of first orbit be minimum?
(A) H atom
(B) ²₁H atom
(C) He⁺ ion
(D) Li²⁺ ion
Answer:

Question 10.
The minimum wavelength of the x-rays produced by electrons accelerated through a potential difference of V(volt) is directly proportional to
(A) \(\sqrt { v } \)
(B) \({ v }^{ 2 }\)
(C) \(\frac { 1 }{ \sqrt { v } } \)
(D) \(\frac { 1 }{ v } \)
Answer:
(D) \(\frac { 1 }{ v } \)

You can Download Chapter 4 Reconstitution of a Partnership Firm – Retirement/Death of a Partner Questions and Answers, Notes, 2nd PUC Accountancy Question Bank with Answers Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.

Karnataka 2nd PUC Accountancy Question Bank Chapter 4 Reconstitution of a Partnership Firm – Retirement/Death of a Partner

2nd PUC Accountancy Reconstitution of a Partnership Firm – Retirement/Death of a Partner NCERT Text Book Questions And Answers

2nd PUC Reconstitution of a Partnership Firm – Retirement/Death of a Partner Short Answer Questions With Answers

Question 1.
What are the different ways in which a partner can retire from the firm.
Answer:
The partner retire from the business for money reasons they are

• Insolvency
• Because of age factor
• Not interested to continue
• All other partner decided

Question 2.
Write the various matters that need adjustments at the time of retirement of a partners.
Answer:
The various accounting aspects involved on retirement or death of a partner are as follows:

• Ascertainment of new profit sharing ratio and gaining ratio;
• Treatment of goodwill;
• Revaluation of assets and liabilities;
• Adjustment in respect of unrecorded assets and liabilities;
• Distribution of accumulated profits and losses;
• Ascertainment of share of profit or loss up to the date of retirement/death;
• Adjustment of capital, if required;
• Settlement of the amounts due to retired/deceased partner;

Question 3.
Distinguish between sacrificing ratio and gaining tab. 218 Accountancy – Not-for-Profit Organisation and Partnership Accounts.
Answer:

Gain ratio	Sacrificing
Acquried from retiring/decreased partner	Give one to new partner
It is calculated at the time retirement or death of partner	It is calculated at the time admission of a partner

Question 4.
Why do firm reyaiuate assets and reassers their liabilities on retirement or on the event of death of a partner.
Answer:
At the time of retirement or death of a partner there may be some assets which may not have been shown at their current values. Similarly, there may be certain liabilities which have been shown at a value different from the obligation to be met by the firm. Not only that, there may be some unrecorded assets and liabilities which need to be brought into books.

As learnt in case of admission of a partner, a Revaluation Account is prepared in order to ascertain net gain (loss) on revaluation of assets and/or liabilities and bringing unrecorded items into firm’s books and the same is transferred to the capital account of all partners including retiring/deceased partners in their old profit sharing ratio.

Question 5.
Why a retiring/deceased partner is entitled to a share of goodwill of the firm.
Answer:
The retiring or deceased partner is entitled to his share of goodwill at the time of retirement” death because the goodwill has been earned by the firm with the efforts of all the existing partners. Hence, at the time of retirement/death of a partner, goodwill is valued as per agreement among the partners the retiring/deceased partner compensated for his share of goodwill by the continuing partners (who have gained due to acquisition of share of profit from the retiring/deceased partner) in their gaining ratio.

2nd PUC Reconstitution of a Partnership Firm – Retirement/Death of a Partner Long Answer Questions With Answers

Question 1.
Explain the modes of payment to a retiring partner.
Answer:
The outgoing partner’s account is settled as per the terms of partnership deed i.e., in lumpsum immediately or in various instalments with or without interest as agreed or partly in cash immediately and partly in installment at the agreed intervals. In the absence of any agreement, Section 37 of the Indian Partnership Act, 1932 is applicable, which states that the outgoing partner has an option to receive either interest @ 6% p.a. till the date of payment or such share of profits which has been earned with his/her money (i.e., based on capital ratio).

Hence, the total amount due to the retiring partner which is ascertained after all adjustments have been made is to be paid immediately to the retiring partner. In case the firm is not in a position to make the payment immediately, the amount due is transferred to the retiring Partner’s Loan Account, and as and when the amount is paid it is debited to his account.

Question 2.
How will you compute the amount payable to a deceased partner?
Answer:
The sum due to the retiring partner (in case of retirement) and to the legal representatives/ executors (in case of death) includes:

• credit balance of his capital account;
• credit balance of his current account(if any);
• his share of goodwill ;
• his share of accumulated profits (reserves);
• his share in the gain of revaluation of assets and liabilities;
• his share of profits up to the date of retirement/death;
• interest on his capital, if involved, up to the date of retirement/death; and
• salary/commission, if any, due to him up to the date of retirement/death.

The following deductions, if any, may have to be made from his share:

• debit balance of his current account(if any);
• his share of goodwill to be written off; if necessary;
• his share of accumulated losses;
• his share of loss on revaluation of assets and liabilities;
• his share of loss up to the date of retirement/death;
• his drawings up to the date of retirement/death;
• interest on drawings, if involved, up to the date of retirement/death.

Question 3.
Explain the treatment of goodwill at the time of retirement or on the event of death of a partner?
Answer:
The retiring or deceased partner is entitled to his share of goodwill at the time of retirement/ death because the goodwill has been earned by the firm with the efforts of all the existing partners. Hence, at the time of retirement/death of a partner, goodwill is valued as per agreement among the partners the retiring/ deceased partner compensated for his share of goodwill by the continuing partners (who have gained due to acquisition of share of profit from the retiring/ deceased partner) in their gaining ratio.

When goodwill does not appear in the books of the firm there are four ways in which the . retiring partner can be given the necessary credit for loss of his share of goodwill, these are as follows:

(a) Goodwill is raised at its full value and retained in the books as such: In this case, Goodwill Account is debited will its full value and all the partner’s (including the retired/deceased partner) capital accounts are credited in the old profit sharing ratio. The full value of goodwill will appear in the balance sheet of the reconstituted firm.

(b) Goodwill is raised at it’s full value and written off immediately: If it decided that goodwill should not be refrained and shown in the balance sheet of the reconstituted firm then, after raising goodwill at its value by crediting all the partners’ capital accounts (including that of the retired/ deceased partners, it should be written off by debiting the remaining partners in their new profit sharing ratio and crediting the goodwill account with its full value.

(c) Goodwill is raised to the extent of retired/deceased partner’s share and written off immediately: In this case goodwill account is raised only to the extent of retired/ deceased partner’s share by debiting goodwill account with the proportionate amount and credited only to the retired/deceased partner’s capital account. Thereafter, the remaining partners capital accounts are debited in their gaining ratio and goodwill account/credited to write it off.

(d) No goodwill account is raised at all in firm’s books: If it is decided that the goodwill account should not appear in firm’s books at all, in that case it is adjusted discretely, through partners capital accounts.

If value of goodwill already appearing in the books of the firm equals with the current value of goodwill, normally no adjustment is required because goodwill stands credited in the accounts of all the partners including the retiring one.

It may be noted that in all the above situations, goodwill appears in the balance sheet at its full value. In case it is decided by the partners that it should be written-off, fully or partially.

Hidden Goodwill: If the firm has agreed to settle the retiring or deceased partner by paying him a lump sum amount, then the amount paid to him in excess of what is due to him based on the balance in his capital account after making necessary adjustments in respect of accumulated profits and losses and revaluation of assets and liabilities, etc. shall be treated as his share of goodwill (known as hidden goodwill).

Question 4.
Discuss the various methods of computing the share in profits in the event of death of a partners.
Answer:
The accounting treatment in the event of death of a partner is similar to that in case of retirement of a partner, and that in case of death of a partner his claim is transferred to his executors and settled in the same manner as that of the retired partner. However, there is one major difference that, while the retirement normally takes place at the end of an accounting period, the death of a partner may occur any time.

Hence, in case of a death, his claim shall also include his share of profit or loss, interest on capital, interest on drawings (if any) from the date of the last Balance Sheet to the date of his death of these, the main problem relates to the calculation of profit for the intervening period (i.e., the period from date of the last balance sheet and the date of the partner’s death.

Since, it is considered cumbersome to close the books and prepare final account, for the period, the deceased partner’s share of profit may be calculated on the basis of last year’s profit (or average of past few years) or on the basis of sales.

2nd PUC Reconstitution of a Partnership Firm – Retirement/Death of a Partner Numerical Questions

Question 1.
Aparna, Manisha and Sonia are partners sharing profits in the ratio of 3 : 2 : 1. Manisha retires and Goodwill of the firm is valued at ₹ 1,80,000. Aparna and Sonia decided to share future in the ratio of 3 : 2. Pass necessary journal entries.
Answer:

Working Notes :
1. Manisha’s share of goodwill:
Total goodwill of the firm × Retiring Partner’s Share, 1,80,000 × \(\frac { 1 }{ 3 }\) = 60,000

2. Gaining Ratio = New Ratio – Old Ratio
Aparna Gaining Share = \(\frac{3}{5}-\frac{3}{6}=\frac{18-15}{30}=\frac{3}{10}\)
Sonia Gaining Share = \(\frac{2}{5}-\frac{1}{6}=\frac{12-5}{30}=\frac{7}{30}\)
Gaining Ratio between Apama and Sonia = 3:7

3. Apama’s share in goodwill = 60,000 × \(\frac { 3 }{ 10 }\) = 18,000
Sonia’s share in goodwill = 60,000 × \(\frac { 7 }{ 10 }\) = 42,000

Question 2.
Sangeeta, Saroj and Shanti are partners sharing profits in the ratio of 2 : 3 : 5. Goodwill is appearing in the books at a value of ₹ 60,000. Sangeeta retires and goodwill is valued at ₹ 90,000. Saroj and Shanti decided to share future profits equally. Record necessary journal entries.
Answer:

Working Notes :
1. Sangeeta’s share of Goodwill.
Total Goodwill of the firm × Retiring Partner’s share ⇒ 90,000 × \(\frac { 2 }{ 10 }\) = 18000

2. Gaining Ratio ⇒ New Ratio – Old Ratio
Saro s Gaming Share = \(\frac{1}{2}-\frac{3}{10}=\frac{10-6}{20}-\frac{4}{20}\)
Shanti’s Gaining Share = \(\frac{1}{2}-\frac{5}{10}=\frac{10-10}{20}=\frac{0}{20}\)

Question 3.
Himanshu, Gagan and Naman are partners sharing profits and losses in the ratio of 3 : 2 : 1. On March 31, 2017, Naman retires. The various assets and liabilities of the firm on the date were as follows:
Cash ₹ 10,000, Building ₹ 1,00,000, Plant and Machinery ₹ 40,000, Stock ₹ 20,000, Debtors ₹ 20,000 and Investments ₹ 30,000.
The following was agreed upon between the partners on Naman’s retirement:

1. Building to be appreciated by 20%.
2. Plant and Machinery to be depreciated by 10%.
3. A provision of 5% on debtors to be created for bad and doubtful debts.
4. Stock was to be valued at ₹18,000 and Investment at ₹ 35,000.

Record the necessary journal entries to the above effect and prepare the revaluation account.
Answer:

Question 4.
Naresh, Raj Kumar and Bishwajeet are equal partners. Raj Kumar decides to retire. On the date of his retirement, the Balance Sheet of the firm showed the following: General Reserves ₹ 36,000 and Profit and Loss Account (Dr.) ₹ 15,000.
Pass the necessary journal entries to the above effect.
Answer:

Question 5.
Digvijay, Brijesh and Parakaram were partners in a firm sharing profits in the ratio of 2:2:1. Their Balance Sheet as on March 31, 2007, was as follows:

Brijesh retired on March 31, 2007, on the following terms:

1. Goodwill of the firm was valued at ₹ 70,000 and was not to appear in the books.
2. Bad debts amounting to ₹ 2,000 were to be written off.
3. Patents were considered as valueless.

Prepare Revaluation Account, Partners’ Capital Accounts and the Balance Sheet of Digvijay and Parakaram after Brijesh’s retirement.
Answer:

Note: As sufficient balance is not available to pay the amount due to Brijesh, the balance of his capital account transferred to his loan account.
Working Note :
1. Brijesh’s share of goodwill
Total goodwill of the firm × Retiring Partner’s Share = 70,000 × \(\frac { 2 }{ 5 }\) = 28,000

2. Gaining Ratio = New Ratio – Old Ratio
Digvijay s = \(\frac{2}{3}-\frac{2}{5}=\frac{10-6}{15}=\frac{4}{15}\)
Parakaram’s = \(\frac{1}{3}-\frac{1}{5}=\frac{5-3}{15}=\frac{2}{15}\)
Gaining ratio between Digvijay and Parakaram = 4 : 2 or 2 : 1.

Question 6.
Radha, Sheela and Meena were in partnership sharing profits in the proportion of 3:2:1. On April 1, 2015, Sheela retires from the firm. On that date, their Balance Sheet was as follows:

The terms were:
(a) Goodwill of the firm was valued at ₹ 13,000.
(b) Expenses owing to be brought down to ₹ 3,750.
(c) Machinery and Loose Tools are to be valued at 10% less than their book value.
(d) Factory premises are to be revalued at ₹ 24,300.
Prepare:
1. Revaluation account
2. Partner’s capital accounts and
3. Balance sheet of the firm after retirement of Sheela.
Answer:

Question 7.
Pankaj, Naresh and Saurabh are partners sharing profits in the ratio of 3:2:1. Naresh retired from the firm due to his illness. On that date the Balance Sheet of the firm was as follows:
Books of Pankaj, Naresh and Saurabh

Additional Information

1. Premises have appreciated by 20%, Stock depreciated by 10% and provision for doubtful debts was to be made 5% on debtors. Further, provision for legal damages is to be made for ₹ 1,200 and furniture to be brought up to ₹ 450.
2. Goodwill of the firm be valued at ₹ 42,000.
3. ₹ 26,000 from Naresh’s Capital account be transferred to his loan account and balance to be paid through bank; if required, necessary loan may be obtained form Bank.
4. New profit sharing ratio of Pankaj and Saurabh is decided to be 5:1.

Give the necessary ledger accounts and Balance sheet of the firm after Naresh’s retirement.
Answer:

Question 8.
Puneet, Pankaj and Pammy are partners in a business sharing profits and losses in the ratio of 2:2:1 respectively. Their Balance sheet as on March 31, 2016, was as follows:

Mr. Pam my died on September 30, 2017. The partnership deed provided the following:

1.The deceased partner will be entitled to his share of profit up to the date of death calculated on the basis of previous year’s profit.
2. He will be entitled to his share of goodwill of the firm calculated on the basis of 3 years’ purchase of average of last 4 years’ profit. The profits for the last four financial years are given below:
for 2012-13; ₹ 80,000;
for 2013-14, ₹ 50,000;
for 2014-15, ₹ 40,000;
for 2015-16, ₹ 30,000.

The drawings of the deceased partner up to the date of death amounted to ₹ 10,000. Interest on capital is to be allowed at 12% per annum. Surviving partners agreed that ₹ 15,400 should be paid to the executors immediately and the balance in four equal yearly instalments with interest at 12% p.a. on outstanding balance. Show Mr. Pammy’s Capital account, his Executor’s account till the settlement of the amount due.
Answer:

Question 9.
Following is the Balance Sheet of Prateek, Rockey and Kushal as on March 31, 2015. Balance Sheet of Prateek, Rockey and Kushal as on March 31, 2015

Rockey died on June 30, 2015. Under the terms of the partnership deed, the executors of a deceased partner were entitled to:
(a) Amount standing to the credit of the Partner’s Capital account.
(b) Interest on capital in 5% per annum.
(c) Share of goodwill on the basis of twice the average of the past three years’ profit and
(d) Share of profit from the closing date of the last financial year to the date of death on the basis of last year’s profit.
Profits for the year ending on March 31, 2013, 2014 and 2015 were ₹ 12,000, ₹ 16,000 and ₹ 14,000 respectively. Profits were shared in the ratio of capitals.
Pass the necessary journal entries and draw up Rockey’s capital account to be rendered to his executor.
Answer:

Question 10.
Narang, Suri and Bajaj are partners in a firm sharing profits and losses in proportion of 1 2,1 6 and 1 3 respectively. The Balance Sheet on April 1, 2015 was as follows: Books of Suri, Narang and Bajaj

Bajaj retires from the Business and the partners agreed to the following:
(a) Freehold premises and stock are to be appreciated by 20% and 15% respectively.
(b) Machinery and Furniture are to be depreciated by 10% and 7% respectively.
(c) Bad Debts reserve is to be increased to ? 1,500.
(d) Goodwill is valued at ₹ 21,000 on Bajaj’s retirement.
(e) The continuing partners have decided to adjust their capitals in their new profit sharing ratio after retirement of Bajaj. Surplus/deficit, if any, in their capital accounts will be adjusted through current accounts.
Prepare necessary ledger accounts and draw the Balance Sheet of the reconstituted firm.
Answer:

Question 11.
The Balance Sheet of Rajesh, Pramod and Nishant who were sharing profits in proportion to their capitals stood as on March 31, 2015:
Books of Rajesh, Pramod and Nishant

Pramod retired on the date of Balance Sheet and the following adjustments were made:
(a) Stock was valued at 10% less than the book value.
(b) Factory buildings were appreciated by 12%.
(c) Reserve for doubtful debts be created up to 5%.
(d) Reserve for legal charges to be made at ₹ 265.
(e) The goodwill of the firm be fixed at ₹ 10,000.
(f) The capital of the new firm be fixed at ₹ 30,000. The continuing partners decide to keep their capitals in the new profit sharing ratio of 3:2.
Pass journal entries and prepare the balance sheet of the reconstituted firm after transferring the balance in Pramod’s Capital account to his loan account.
Answer:

Question 12.
Following is the Balance Sheet of Jain, Gupta and Malik as on March 31, 2016. Books of Jain, Gupta and Malik

The partners have been sharing profits in the ratio of 5:3:2. Malik decides to retire from business on April 1, 2016 and his share in the business is to be calculated as per the following terms of revaluation of assets and liabilities: Stock, ₹ 20,000; Office furniture, ₹ 14,250; Plant and Machinery ₹ 23,530; Land and Building ₹ 20,000. A provision of ₹ 1,700 to be created for doubtful debts. The goodwill of the firm is valued at ₹ 9,000.

The continuing partners agreed to pay ₹ 16,500 as cash on retirement of Malik, to be contributed by continuing partners in the ratio of 3:2. The balance in the capital account of Malik will be treated as loan.
Prepare Revaluation account, capital accounts, and Balance Sheet of the reconstituted firm.
Answer:

Question 13.
Arti, Bharti and Seema are partners sharing profits in the proportion of 3:2:1 and their Balance Sheet as on March 31, 2016 stood as follows :
Books of Arti, Bharti and Seema

Bharti died on June 12, 2016, and according to the deed of the said partnership, her executors are entitled to be paid as under :
(a) The capital to her credit at the time of her death and interest thereon @ 10% per annum.
(b) Her proportionate share of reserve fund.
(c) Her share of profits for the intervening period will be based on the sales during that period, which were calculated as ₹ 1,00,000. The rate of profit during past three years had been 10% on sales.
(d) Goodwill according to her share of profit to be calculated by taking twice the amount of the average profit of the last three years less 20%. The profits of the previous years were :
2013-₹8,200
2014.-₹9,000
2015-₹9,800
The investments were sold for ₹16,200 and her executors were paid out. Pass the necessary journal entries and write the account of the executors of Bharti.
Answer:

Question 14.
Nithya, Sathya and Mithya were partners sharing profits and losses in the ratio of 5:3:2. Their Balance Sheet as on March 31,2017 was as follows :
Books of Nithya, Sathya and Mithya

Mithya dies on August 1, 2018. The agreement between the executors of Mithya and the partners stated that:
(a) Goodwill of the firm be valued at 2 1/2 times the average profits of last four years. The profits of four years were : in 2014,₹ 13,000; in 2015, ₹ 12,000; in 2016, ₹ 16,000; and in 2017, ₹ 15,000.
(b) The patents are to be valued at ₹8,000, Machinery at ₹25,000 and Premises at ₹25,000.
(c) The share of profit of Mithya should be calculated on the basis of the profit of 2015.
(d) ₹ 4,200 should be paid immediately and the balance should be paid in 4 equal half-yearly instalments carrying interest @ 10%.
Record the necessary journal entries to give effect to the above and write the executor’s account till the amount is fully paid. Also prepare the Balance Sheet of Nithya and Sathya as it would appear on August 1, 2015, after giving effect to the adjustments.
Answer:

Test your Understanding -1

Choose the correct option in the following questions:

Question 1.
Abhishek, Rajat and Vivek are partners sharing profits in the ratio of 5:3:2. If Vivek retires, the New Profit Sharing Ratio between Abhishek and Rajat will be
(a) 3:2
(b) 5:3
(c) 5:2
(d) None of these
Answer:
(b) 5:3

Question 2.
The old profit sharing ratio among Rajender, Satish and Tejpal were 2:2:1. The New Profit Sharing Ratio after Satish’s retirement is 3:2. The gaining ratio is
(a) 3:2
(b)2:1
(c) 1:1
(d) 2:2
Answer:
(c) 1:1

Question 3.
Anand, Bahadur and Chander are partners. Sharing Profit equally On Chander’s retirement, his share is acquired by Anand and Bahadur in the ratio of 3:2. The New Profit Sharing Ratio between Anand and Bahadur will be-
(a) 8:7
(b) 4:5
(c)3:2
(d) 2:3
Answer:
(c). 3:2

Question 4.
In the absence of any information regarding the acquisition of share in profit of the retiring/deceased partner by the remaining partners, it is assumed that they will acquire his/her share:-
(a) Old Profit Sharing Ratio
(b) New Profit Sharing Ratio
(c) Equal Ratio
(d) None of these
Answer:
(a) Old Profit Sharing Ratio

You can Download Chapter 9 Money And Banking Questions and Answers, Notes, 2nd PUC Economics Question Bank with Answers Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.

Karnataka 2nd PUC Economics Question Bank Chapter 9 Money And Banking

2nd PUC Economics Money And Banking One Mark Questions and Answers

Question 1.
Write the meaning of Barter System.
Answer:
Exchange of goods for goods is called as Barter System.

Question 2.
What is money?
Answer:
Money is anything which is commonly accepted as a medium of exchange for goods and services and acts as a measure of value.

Question 3.
Define Money.
Answer:
According to F. A. Walker “Money is what money does”.

Question 4.
Write any two Primary functions of money.
Answer:
The two primary functions of Money are  (a) Medium of exchange (b) Measure of value.

Question 5.
What is high powered money?
Answer:
The high powered money refers to that money which is held by the public, demand deposits of banks and other deposits held by the Reserve Bank of India.

Question 6.
What is demand for money?
Answer:
The demand for money includes the sum of transactionary demand for money, precautionary demand for money and speculative demand for money.

Question 7.
Write the meaning of supply of money.
Answer:
The supply of money refers to the total currency notes and coins held by the people in the country at a particular point of time. In other words, it refers to the aggregate stock of money.

Question 8.
Expand ATM.
Answer:
Automated Teller Machine.

Question 9.
What is narrow money?
Answer:
The money which is fully liquid and available whenever people need is called narrow money.

Question 10.
What is broad money?
Answer:
Broad money refers to the money held by the public in the form of savings and Net Time Deposits apart from the currency and demand deposits.

Question 11.
What do you mean by Primary Deposit?
Answer:
When a bank accepts cash from the customer and opens an account in the name of that customer, it is called a Primary Deposit.

Question 12.
What is bank rate?
Answer:
Bank rate is the rate of interest charged by the Reserve Bank of India while lending loans and advances to commercial banks.

Question 13.
What is overdraft?
Answer:
It is a facility provided by a bank to its current account holders to overdraw their accounts upto certain limit.

Question 14.
What is cash reserve ratio (CRR)?
Answer:
The CRR is a certain percentage of bank deposits which commercial banks are required to keep with the RBI in the form of reserve funds.

Question 15.
What do you mean by Statutory Liquidity Ratio (SLR)?
Answer:
There is an RBI directive to commercial banks to maintain a certain percentage of their total demand and time deposits with themselves, in the form of liquid assets like cash, precious metals or approved securities like bonds. The ratio of the liquid assets to time and demand liquidities is termed as SLR which is 22.5% at present.

Question 16.
What is Precautionary motive of money?
Answer:
The demand for money to meet the unforeseen and unexpected expenses is known as precautionary demand for money.

2nd PUC Economics Money And Banking Two Marks Questions and Answers

Question 1.
Mention any four difficulties of Barter system.
Answer:
The four major difficulties of barter system are:

1. Lack of double coincidence of wants.
2. Lack of common measure of value.
3. Lack bf divisibility.
4. Difficulty in storing wealth.

Question 2.
State the differences between narrow money and broad money.
Answer:

Narrow money	Broad money
(i) It is highly liquid money.	(i) It includes both full liquid and less liquid money.
(ii) It includes coins and currency notes with public, demand deposits with banks and other deposits with RBI.	(ii) It includes money held in the form of savings, net time deposits, currency and demand deposits.
(iii) It is represented as MN=C+DD+OD	(iii) It is represented as MB = C+DD+SD+TD

Question 3.
Distinguish between Primary deposits and Derivative deposits.
Answer:

Primary Deposits	Derivative Deposits
(i) It is created when customers deposit their money in the bank by opening new accounts.	(i) It arises when customers are granted loans and advances by a bank.
(ii) It does not create any kind of credit creation.	(ii) It contributes directly towards credit creation activity of commercial banks
(iii) Whenever customer makes payment to the banks, primary deposits are created	(iii) Whenever the loan is granted, derivate deposit is created.

Question 4.
Mention the motives of demand for money as per J.M.Keynes.
Answer:
According to J.M.Keynes, the three motives of demand for money are as follows:

• Transaction motive
• Precautionary motive and
• Speculative motive.

Question 5.
State the various types of deposits.
Answer:
The types of deposits are as follows:

1. Current account deposits
2. Savings account deposits.
3. Fixed Deposits
4. Recurring Deposits.

Question 6.
Write the four objectives of monetary policy.
Answer:
The four objectives of monetary policy are as follows:

1. To establish Exchange rate stability.
2. To achieve Price stability.
3. To control business cycles.
4. To provide full employment.

Question 7.
What do you mean by open market operations?
Answer:
Open market operation is an instrument of monetary policy which involves buying and selling of Government securities in the open market between RBI and other commercial banks and the public. RBI sells Government securities to decrease the flow of credit and buys them back to increase credit flow, as the situation warrants.

Question 8.
Distinguish between Scheduled and non-scheduled commercial banks.

Scheduled Banks	Non-Scheduled Banks
These banks are those which are included in second schedule of RBI Act 1934.	These are the banks which are not included in the second schedule of RBI Act 1934.
The paid up capital and reserve fund is more than Rs.5,00,000.	The paid up capital and reserve fund is less than Rs.5,00,000.

Question 9.
What are the contingent functions of Money?
Answer:
The contingent functions of money are as follows:

• Distribution of National Income.
• Basis of credit.
• Maximizes the satisfaction of both consumers and producers.
• Gives liquidity to wealth.

Question 10.
Mention various types of loans and advances of Commercial Banks.
Answer:
The major types of loans and advances are Overdraft, Cash Credit, Loans and Discounting of Bills of Exchange.

2nd PUC Economics Money And Banking Five Marks Questions and Answers

Question 1.
Briefly explain the Primary functions of Money.
Answer:
The primary functions of money are as follows:
a) Medium of Exchange: Money plays an important role as a medium of exchange. It facilitates exchange of goods for money. It has solved the problems of barter system. It helps the people to sell in one place and buy in another place. Money has widened the scope of market transactions. Money has become a circulating material between buyers and sellers.

b) Measure of Value: The money acts as a common measure of value. The values of all goods and services can be expressed in terms of money. As a measure of value, money performs following functions:

• The value of all goods and services measured and expressed in terms of the money.
• Rate of exchange of goods and services expressed in money.
• Facilitates the maintenance of accounts.
• It facilitates price mechanism.
• It makes goods and services comparable in terms of price.

Question 2.
Write a note on the supply of money.
Answer:
The supply of money is the total of all forms of money held by the community at any particular point of time. Milton Friedman defines the money supply at any moment of time as ‘Literally the number of dollars they have to their credit at banks or in the forms of demand deposits and also commercial bank time deposits’.

The RBI working group on money supply has modified the parameters of measuring money supply in the form of NM₁, NM₂ and NM₃.
NM₁ = Currency with the public + demand deposits with the banking system + other deposits with the RBI
NM₂ = NM₁ + short term time deposits of the public
NM₃ = NM₂ + long term time deposits of the public + term funding from financial institutions.

Narrow Money and Broad Money :
Narrow Money:
It is highly liquid money. It includes coins and currency notes with public, demand deposits with banks and other deposits with RBI. It is represented as M_N = C + DD + OD

Broad Money:
It includes both full liquid and less liquid money.
It includes money held in the form of savings, net time deposits, currency and demand deposits. It is represented as M_b = C+ DD + SD + TD.

Question 3.
Briefly explain the quantitative methods of Credit control.
Answer:
As per Banking Regulation act of 1949, “RBI has the power to adopt and implement various credit control measures to achieve objectives like proper regulation of volume of credit and prices. Different quantitative measures implemented by RBI are as follows:

a) Bank Rate Policy: It is the standard rate at which RBI is prepared to buy or re-discount bills of exchange or commercial papers eligible for purchase according to the banking regulation act. It is the rate at which RBI extents advances to commercial banks. This influences the lending rates of commercial banks. Earlier in 1991 the rate was 12% and as on 2005, it was 6% and it was 5.5% in 2008.

b) Open Market Operations: It refers to purchase and sale of various assets like gold, Government securities, foreign exchange, etc by RBI. The expansion and control of supply of money is done by “Open market operations”. RBI purchases securities during deflation arid sells them during inflation.

c) Variable reserve requirements: As per the banking regulation act, every bank has to keep certain percentage of its total deposits with RBI in the form of reserve fund. By changing the ratio (increase or decrease) of these reserves, RBI can control- the credit power of banks.

These variable requirements are of two types. They are Cash reserve ratio (CRR) and Statutory liquidity ratio (SLR):
i) Cash reserve ratio (CRR): It is the portion of total deposits of the commercial banks . which they have to keep with RBI in the form known as cash reserves. At present CRR is at 5% as of 21^st January 2005.

ii) Statutory liquidity ratio (SLR): It is the portion of total deposits of commercial banks which they have to keep with themselves and these deposits must not be Used for credit purpose. In other words, SLR refers to that portion of total deposits which a commercial bank has to keep with itself in the form of liquid assets viz., cash, gold or approved Government securities. The SLR has been reduced to 25% on the entire net demand. This is as per the recommendations of Narasimham committee.

Question 4.
Explain the qualitative or selective methods of credit control.
Answer:
Selective credit controls are those measures used by RBI along with other measures to control credit. It is used as the supplement to the regular credit regulations. The selective credit controls used by RBI are as follows:

a) Fixation of margin requirements: A central bank changes the margin requirement from time to time to regulate the volume of the credit. The difference between the market value of securities or assents and the amount actually lent against these securities is called margin. The RBI may increase the margin to reduce the volume of credit and decrease the margin to expand the credit.

b) Regulation of Consumer credit: Consumer credit refers to financial assistance given by banks to consumer to purchase vehicles, electronic goods, electrical items etc. In order to avoid demand pull inflation, the RBI regulates the consumer’s credit.

c) Moral Suasion: It implies that persuasion and request made by the Central Bank to Commercial Banks to cooperate with the general monetary policy.

d) Direction action: The RBI may take direct action against the erring commercial banks by refusing to rediscount their commercial bills and may charge penal rate of interest.

e) Credit Rationing: The RBI through its credit rationing system, directs the commercial banks to borrow loans to a certain limit. In turn, the commercial banks will lend loans to limited sector and there the supply of money gets controlled.

f) Publicity: The RBI gives regular publicity about money market trends, educates the commercial banks to regulate the credit. It includes publishing the monthly review of credit and business conditions and the annual reports on the banking sectors.

Question 5.
Explain the objectives of Monetary Policy.
Answer:
According to R.P. Kent, monetary policy is ‘the management of the expansion and contraction of volume of money in circulation for the explicit purpose of attaining specific objectives’.

The main objectives of Monetary policy are as follows:
a) To stabilize money market: The main objective of monetary policy is to stabilize the money market and to reduce the fluctuations in the interest rates to the minimum. The neutral monetary policy should be introduced to achieve the equilibrium in the demand and supply of money.

b) To stabilize the Exchange rate: The unstable exchange rate in international market is not favourable for the foreign trade of a country. The central tries to bring stability in foreign exchange rate through controlling credit creation activities of commercial banks.

c) To stabilize Price level: Price stability is an important objective of monetary policy. The fluctuation in price level leads to ups and downs in business. The RBI, through its monetary policy controls the inflationary situations.

d) To control business or trade cycles: The Business cycles are ups and downs in business. Existence of business cycle brings instability in economy. It is one of the objectives of monetary policy of RBI to control business cycles and bring stability.

e) Full employment: The economic stability with full employment and high per capita income has been considered as an important objective of monetary policy. In order to achieve the objective of full employment, cheap monetary policy should be made applicable.

Question 6.
Explain the primary functions of Commercial Banks.
Answer:
Commercial banks play a major role, in the economic development of a country. They are the backbone of investment activities. They perform many functions. The primary functions of commercial banks are as follows:

a) Accept Deposits: The main function of commercial hanks is accepting deposits. They maintain different types of deposits from the public. They are as follows:
(i) Current account deposits: These are the deposits payable on demand. Money can be withdrawn any number of times as per the desires of depositors. Usually, no interest is paid. The current account deposits are meant for traders and businessmen. Such deposits are also called as demand deposits.

(ii) Savings account deposits: Savings deposit accounts are generally opened by the people of low income, salary earners and others. The banks impose certain restrictions on the withdrawal of amount. Low rate of interest is paid on these deposits. This type of deposits encourage small savings in the society.

(iii) Fixed deposits: These are the deposits in which money deposited is fixed for a period of time and cannot be withdrawn before the stipulated time. Higher rate of interest is paid. Interest rate depends on the duration of deposit. Higher interest is paid for longer duration and vice versa. Such deposits are also called as Time deposits.

(iv) Recurring Deposits: Under these deposits, customer deposits money regularly in monthly installments for period of one year or more. After the stipulated time period, the total amount deposited is paid to the customer along with interest. The rate of interest is higher when compared to savings account deposits.

(b) Provide Loans: Providing loans to customers is another important primary function of commercial banks. They provide several types of loans and advances. They are as follows:
(i) Overdraft: It is a facility provided by a bank to its current account holders to overdraw their accounts upto a certain limit. Interest is charged on the amount actually overdrawn by the customer. This type of loan is provided to businessmen and joint stock companies.

(ii) Cash Credit: This type of loan is given to the customers against the assets like shares, stocks, bonds, etc. Under this scheme, the customer is allowed to withdraw the amount up to a certain limit in accordance with the value of the assets he possessed. Interest is charged only on the amount which is withdrawn.

(iii) Loans: Under this type, commercial banks provide specified sum of money to a person or firm against surety or security of an asset, movable or immovable. Loans are given to a borrower by crediting the loan amount to the new account opened by the banker. The borrower can withdraw money as per his needs. The interest is charged on the whole loan amount which is sanctioned by the banker.

(iv) Discounting of bills of exchange: Discounting of bills of exchange refers to encashing, the commercial bills from the banks before the date of maturity. The banks charge some commission while discounting bills of exchange. Here, the loans are given as advance payment against the bills payable.

Question 7.
What are commercial banks? Explain the types of Commercial banks.
Answer:
Commercial banks are those banks which accept deposits from public and lend loans to public. They perform all kinds of banking business and generally finance trade and commerce. They deal in money and credit.

The major features of a Commercial bank are as follows:

• It accepts deposits and lends loans.
• It deals in credit and it has ability to create credit.
• It is a commercial financial institution which tries to get profit.
• It creates demand deposits which serve as a medium of exchange.

According to RBI ACT, 1934, Indian commercial banks are classified as follows:
a) Scheduled Banks: These are the banks which are included in the second schedule of RBI Act, 1934. Their paid up capital is more than Rs.5 lakhs.

b) Non-Scheduled Banks: These are those commercial banks which are not included in second schedule of RBI Act, 1934. Their paidup capital is less than Rs.5 lakhs.

The commercial banks are classified on the basis of ownership as follows:
a) Public Sector Banks: The banks which are owned and managed by the Government are called as Public Sector Banks, e.g. State Bank of India, State Bank of Mysore, Canara Bank, Punjab National Bank, etc.

b) Private Sector Banks: The banks which are owned and managed by the private individuals or companies. They consists of both Indian and foreign private banks.

2nd PUC Economics Money And Banking Ten Marks Questions and Answers

Question 1.
Explain the functions of money.
Answer:
The functions of Money are broadly classified as follows:
I. Primary functions
II. Secondary functions
III. Contingent functions and
IV. other functions

I. Primary Functions:
The primary functions of money are as follows:
a) Medium of Exchange: Money plays an important role as a medium of exchange. It facilitates exchange of goods for money. It has solved the problems of barter system. It helps the people to sell in one place and buy in another place. Money has widened the scope of market transactions. Money has become a circulating material between buyers and sellers.

b) Measure of value: The money acts as a common measure of value. The values of all goods and services can be expressed in terms of money. As a measure of value, money performs the following functions:

• The value of all goods and services are measured and expressed in terms of money.
• Rate of exchange of goods and services expressed in money.
• Facilitates the maintenance of accounts.
• It facilitates price mechanism.
• It makes goods and services comparable in terms of price.

II. Secondary functions: The secondary functions of money are as follows:
a) Store of value: People can save part of their present income and hold the same for future. Money can be stored for precautionary motives needed to overcome financial stringencies.

b) Standard of deferred payments: All the credit transactions are expressed in terms of money. The payment can be delayed or postponed. So, money can be used for delayed settlement of dues or financial commitments.

c) Transfer of value: Money acts as a transfer of value from person to person and from place to place. As a transfer of value, money helps us to buy goods, properties or anything from any part of the country or the world. Further, money earned in different places can be brought or transferred to anywhere in the world.

III. Contingent Functions of Money:
Other than Primary and Secondary functions, money also performs other functions which are as follows:
a) Basis of Credit: Money serves as a basis of the credit. The modern credit system exists only because of existence of money.

b) Distribution of National Income: Money helps in distribution of national income. The reward paid to factors of production in the form of rent, wages, interest and profit are nothing but the distribution of National Income at factor prices.

c) Provides Liquidity and Uniformity: Money provides liquidity to all kinds of assets both movable and immovable. Money can be converted into any type of asset and all assets can be converted into money.

d) Helps in consumers’ and producers’ equilibrium: All goods and services are expressed in terms of money. The consumer attains equilibrium when the price of a product is equal to his marginal utility. Similarly, the producers reach equilibrium if they get maximum satisfaction. Both consumers and producers try to achieve equilibrium with the help of money.

IV. Other functions of money:

a) Money helps in decision making.
b) Helps the Government in collection of taxes and undertaking expenditure.
c) The solvency of a person can be determined with the help of money.
d)Money helps in determining purchasing power of rich or poor.

Question 2.
Explain the three motives of Demand for Money.
Answer:
Demand for money refers to desire to hold money for.fulfilling different requirements. People keep money for day-to-day activities, to meet consequential expenses and to invest on shares and debentures. J.M.Keynes, in his General Theory used a new term ‘liquidity preference’ for the demand for money. J.M.Keynes suggested three motives which led to the demand for money in an economy. They are as follows:

a) Transaction demand for money: When people hold cash to meet daily transactions is called transaction demand for money. The transaction motive relates to the demand for money for the day to day expenditure of individuals and business firms. The need for holding cash arises due to a time gap between receipt of income and the consumption expenditure. As income increases, people like to spend more and in turn they demand more money to hold. The Transaction demand for money is represented as follows:
M^d_T = f (Y) where, M^d_T represents the transaction demand for money, Y represents the income of an individual and T represents functional relationship between two variables.

b) Precautionary Motive: People keep money to meet unexpected expenses or circumstances, e.g. people hold cash to meet medical treatment, accidents, emergencies, to perform some rituals or celebrations etc. We need to hold cash for meeting such emergencies in our life. If we demand money for such needs, it is known as precautionary demand for money. As income rises, precautionary demand for money also gets increased and if the income falls, the precautionary demand for money also falls. This can be expressed as follows:

M^d_p = f (Y), where M^dp represents the precautionary demand for money, Y represents the income of an individual and ‘f’ represents functional relationship between two variables.

c) Speculative Motive: Some people hold cash to invest on shares, debentures, gold, immovable properties etc. The speculative demand for money refers to the demand for money that people hold as idle cash to speculate with the aim of earning capital gains and profits. According to J.M.Keynes there will be inverse relationship between the rate of interest and speculative demand for money. If the rate of interest is low the people desire to keep more cash with them and vice versa. So, the speculative demand for money is inversely related to the expected rate of interest. This can be expressed as follows:

M^d_s = f (i_e), where M^ds represents the Speculative demand for money, (i_e), represents the expected rate of interest, and ‘f ’ represents functional relationship between two variables.

Question 3.
Explain the functions of Commercial Banks.
Answer:
Commercial banks play a major role in the economic development of a country. They are the backbone of investment activities. They perform many functions. The functions commercial banks are classified as Primary functions and Secondary Functions.

I. Primary Function:
The primary functions of commercial banks are as follows:

a) Accept Deposits: The main function of commercial banks is accepting deposits. They maintain , different types of deposits from the public. They are as follows:

i) Current account deposits: These are the deposits payable on demand. Money can be withdrawn any number of times as per the desires of depositors. Usually, no interest is paid. The current account deposits are meant for traders and businessmen. Such deposits are also called as demand deposits.

ii) Savings account deposits: Savings deposit accounts are generally opened by the people of low income, salary earners and others. The banks impose certain restrictions on the withdrawal of amount. Low rate of interest is paid on these deposits. This type of deposits encourage small savings in the society.

iii) Fixed deposits: These are the deposits in which money deposited is fixed for a period of time and cannot be withdrawn before stipulated time. Higher rate of interest is paid. Interest rate depends on the duration of deposit. Higher interest is paid for longer duration and vice versa. Such deposits are also called as Time deposits.

iv) Recurring Deposits: Under these deposits, customer deposits money regularly in monthly installments for period of one year or more. After the stipulated time period, the total amount deposited is paid to the customer along with interest. The rate of interest is higher when compared to savings account deposits.

b) Provide Loans: Providing loans to customers is another important primary function of commercial banks. They provide several types of loans and advances. They are as follows:

i) Overdraft: It is a facility provided by a bank to its current account holders to overdraw their accounts upto a certain limit. Interest is charged on the amount actually overdrawn by the customer. This type of loan is provided to businessmen and joint stock companies.

ii) Cash Credit: This type of loan is given to the customers against the assets like shares, stocks, bonds, etc. Under this scheme, the customer is allowed to withdraw the amount up to a certain limit in accordance with the value of the assets he possessed. Interest is charged only on the amount which is withdrawn.

iii) Loans: Under this type, commercial banks provide specified sum of money to a person or firm against surety or security of an asset, movable or immovable. Loans are given to a borrower by crediting the loan amount to the new account opened by the banker. The borrower can withdraw money as per his needs. The interest is charged on the whole loan amount which is sanctioned by the banker.

iv) Discounting of bills of exchange: Discounting of bills of exchange refers,to encashing the commercial bills from the banks before the date of maturity. The banks charge some commission while discounting bills of exchange. Here, the loans are given as advance payment against the bills payable.

II Secondary Functions:

The secondary functions of commercial banks are as follows:

a) Agency functions: The commercial banks act as agents to their customers in various money transactions. On behalf of their customers they make payments and accept deposits.
b) General Services: The commercial banks are also providing general utility services like electronic fund transfer, Automated Teller machine, e-banking, merchant banking, mobile banking, etc.

Question 4.
What is credit creation? How do the banks create credit?
Answer:
The creation of credit or deposits is one of the most important functions of commercial banks. Credit creation is a process in which expansion of bank deposits takes place along with the investments in the form of loans and advances. Like other companies, the banks also aim at earning profits. For this purpose, they accept cash in demand deposits and advance loans on credit to customers. According to R.S.Sayers, “Banks are not merely purveyors of money but also manufacturer of money”.

The bank loan is not paid directly to the borrower but is only credited to his account and allows him to withdraw the required cash. Every loan creates its own deposits in the bank., So. the credit is created by the bank by expanding its deposits.

The bank deposits are created in two ways. They are as follows:

• Primary Deposits: This type of deposit is created when the bank accept deposits from the public. The primary deposits act as base for providing loans to the public.
• Derivative Deposits: These deposits arise when banks lend loans to customers. The bank loan is not paid directly to the borrower but is only credited to his account and allows him to withdraw the required cash. So, whenever a loan is granted, derivative deposit is created by the bank.

Credit creation by commercial Banks:
The process of credit creation starts with banks lending money from primary deposits. Banks lend money after keeping certain portion of primary deposits in the form of reserves as per the directions of the Central Bank. The following assumptions are assumed to illustrate the process of credit creation by commercial banks.

• Existence of many banks in the country.
• Every bank has to maintain 10% cash reserve.
• Initial deposit of Rs. 1000 is made by the customer into the bank.
• Existence of banking habits.

with the above assumptions, if a Canara Bank receives Cash deposits of Rs.1000 from a customer. Given the reserve ratio of 10%, the bank keeps Rs. 100 in reserves and provide loan of Rs.900 to Mr.A. The balance sheet of Canara Bank will be as

When Canara bank lends Rs.900 to Mr.A, he may deposit it with the same bank or some other bank. If the deposits Rs.900 with Vijaya Bank, then Vijaya Bank receives Rs.900 as initial deposit called Primary deposit. By keeping 10% reserve i.e., Rs.90, it can lent Rs.810 to Mr.B. Then the balance sheet of Vijaya Bank will be as follows:

Thus the process will continue till the primary deposit of Rs. 1000 is fully used in the process of credit. The cash deposit of Rs. 1000 results in a derivative deposit of Rs.900+810+………and so on. The following table shows the whole banking system’s credit creation activity:

Question 5.
Explain the functions of Reserve Bank of India.
Answer:
RBI is the Apex Bank in the country. It was established on 1^st April 1935. It was started as private shareholders bank. After independence, Government of India nationalized it and made it as the central bank. It is the head of all banks and financial institutions.

Mumbai is the head Office of RBI. RBI has its regional offices in Delhi, Kolkata, Mumbai and Chennai. It also has its branches in Bengaluru, Hyderabad, Lucknow and Kanpur. The present Governor of R.B.I is Dr. Subba Rao.

Functions of RBI:
The main functions of RBI are as follows:
It is the central bank of the country. Like any other central banks which operate in different countries, RBI functions in the same manner. It basically performs three functions.

They are
I. Traditional and primary functions.
II. Development functions and
III. Other functions.

I Traditional and primary functions of RBI are as follows:
1. Printing and issuing currency notes: It has complete authority of printing and issuing currency notes in the country. RBI issue all denominations, of currency notes (Rs. 2, Rs. 10, Rs. 20, Rs. 50, Rs. 100, Rs. 500 and Rs. 1000) except one rupee note, which is issued by Finance Ministry of Central Government Minimum reserve system of note issue was followed by RBI after 1956.

2. Banker to Government: RBI works as banker to the Government. It does all activities of banking on behalf of government activities like opening account, receiving money, making payments, transfer government funds, manages public debt and also maintains accounts of expenditure of.government. It also gives credit to government Relating to financial matters, RBI gives advise to Government.

RBI also acts as agent to the Government through performing the transfer of funds from Government to beneficiaries.
RBI also advises the Government during some circumstances like not to go for over expenditure during inflation.

3. Act as Bankers’ bank: All banks and financial institutions in India are under the control of RBI. It advices and gives direction on all transactions of commercial banks. All commercial banks in India have to keep certain portion of its deposits as cash reserves with RBI. All commercial banks have to submit a detailed document and report about its transactions to RBI.

As a banker’s bank RBI functions as follows:

• Lender of last resort: RBI provides financial assistance to commercial banks like giving credit, discounting bills, giving advances, etc during their financial crisis and helps the banks as a lender of last resort.
• Clearing House: Commercial Banks in crisis can approach RBI for loans and advances. RBI re-discounts bills and lends money to commercial banks. It also advances money on other securities.

4. Controls credit creation activities of commercial banks: The credit provided by all commercial banks is controlled by RBI. RBI implements both Quantitative and qualitative techniques to control the credit generated by commercial banks. The quantitative measures to control credit are Bank rate policy, Open market operation, Cash reserve ratio and Statutory liquidity ratio. The qualitative techniques of credit control include fixation of margin requirements for loans, introduction of a system of credit rationing, moral suasion and Direct action.

5. Controls money market: RBI is the leader of money market. All the activities and components of money market like commercial banks and financial institutions are controlled and directed by RBI.

6. In-charge of foreign exchange reserves: RBI has regular and continuous contacts with international monetary institutions relating to foreign exchange reserves. Precious foreign exchanges is preserved and protected by it.

II Developmental functions performed by RBI are as follows:

• Finance to agriculture: A separate department in RBI is engaged in providing credit and advances to agricultural sector indirectly. It operates through NABARD (National Bank for Agriculture and Rural Development) and state co-operative banks. It has taken steps to develop and reorganize co-operative societies.
• Financing industries: RBI has taken lot of interest in establishment and development of industries. Various financial institutions like IDBI, ICICI, SFC and IFC are established by RBI to cater the financial needs of industries.

III Other functions:

1. Special functions:

•  It gives training facilities to bank staff.
• It conducts seminars and debates on various subjects.
• It has regular and continuous contact with international monetary institutions and takes steps to improve co-
• operative movement in the country.
• It studies various problems in agriculture, industry and provides ideal solutions to it.

2. Research functions of RBI are as follows:

• It collects information on different sectors of the economy.
• It issues periodicals regularly.
• It issues special bulletins on various issues like supply of finance, financial matters of both Central and State Governments.

Question 6.
Discuss the instruments of Monetary policy of Reserve Bank of India.
Answer:
As per Banking Regulation act of 1949, RBI has the power to adopt and implement various credit control measures to achieve objectives like proper regulation of volume of credit and prices. The instruments of Monetary policy of RBI are as follows:

I. Quantitative measures: The quantitative methods of credit control implemented by RBI are as follows:
a) Bank Rate Policy: It is the standard rate at which RBI is prepared to buy or rediscount bills of exchange or commercial papers eligible for purchase according to the banking regulation act. It is the rate at which RBI extents advances to commercial banks. This influences the lending rates of commercial banks. Earlier in 1991 the rate was 12% and as on 2005, it was 6% and it was 5.5% in 2008.

b) Open Market Operations: It refers to purchase and sale of various assets like gold, Government securities, foreign exchange, etc by RBI. The expansion and control of supply of money is done by “Open market operations”. RBI purchases securities during deflation
and sells during inflation.

c) Variable reserve requirements As per the banking regulation act, every bank has to keep certain percentage of its total deposits with RBI in the form of reserve fund. By changing the ratio (increase or decrease) of these reserves, RBI can control the credit power of banks.

These variable requirements are of two types. They are Cash reserve ratio (CRR) and Statutory liquidity ratio (SLR):
(1) Cash reserve ratio (CRR): It is the portion of total deposits of the commercial banks which has to keep with RBI in the form known as cash reserves. At present CRR is at 5% as on 21^st January 2005.

(2) Statutory liquidity ratio (SLR): It is the portion of total deposits of commercial banks which they have to keep with them selves and these deposits must not be used for credit purpose. In other words, SLR refers to that portion of total deposits which a commercial bank has to keep with it self in the form of liquid assets viz., cash, gold or approved Government securities. The SLR has been reduced to 25% on the entire net demand. This is as per the recommendations of Narasimham committee.

II. Selective credit controls: These are those measures used by RBI along with other measures to control credit. It is used as the supplement to the regular credit regulations. The selective credit controls used by RBI are as follows:

a) Fixation of margin requirements: A central bank changes the margin requirement from time to time to regulate the volume of the credit. The difference between the market value of securities or assents and the amount actually lent against these securities is called margin. The RBI may increase the margin to reduce the volume of credit and decrease the margin to expand the credit.

b) Regulation of Consumer credit: Consumer credit refers to financial assistance given by banks to consumer to purchase vehicles, electronic goods, electric items etc. In order to avoid demand pull inflation, the RBI regulates the consumer’s credit.

c) Moral suasion: It implies that persuasion and request made by the Central Bank to Commercial Banks to cooperate with the general monetary policy.

d) Direction action: The RBI may take direct action against the erring commercial banks by refusing to rediscount their commercial bills and may charge penal rate of interest.

e) Credit Rationing: The RBI through its credit rationing system, directs the commercial banks to borrow loans to a certain limit. In turn, the commercial banks will lend loans to limited sector and there the supply of money gets controlled.

f) Publicity: The RBI gives regular publicity about money market trends, educates the commercial banks to regulate the credit. It includes publishing the monthly review of credit and business conditions and the annual reports on the banking sectors.

You can Download Chapter 10 Wave Optics Questions and Answers, Notes, 2nd PUC Physics Question Bank with Answers, Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.

Karnataka 2nd PUC Physics Question Bank Chapter 10 Wave Optics

2nd PUC Physics Wave Optics NCERT Text Book Questions and Answers

Question 1.
Monochromatic light of wavelength 589 nm is incident from air on a water surface. What are the wavelength, frequency and speed of
(a) reflected, and
(b) refracted light? Refractive index of water is 1.33.
Answer:
\({ ^{ a }{ \mu } }_{ W }\)=1.33
\({ { \lambda } }_{ air }=589nm=589\times { 10 }^{ -9 }\)
(a) For reflected light:- On reflection, no change occurs in wavelength, frequency and speed of the incident light.
Velocity of the reflected light = 3 x 10⁸ ms^-1
wavelength of the reflected light = 589 nm

The frequency is a inherent characteristic of radiation. It does not change on refraction.
∴ Frequency of the refracted light = 5.09 x 10¹⁴Hz.

Question 2.
What is the shape of the wavefront in each of the following cases:
(a) Light diverging from a point source.
(b) Light emerging out of a convex lens when a point source is placed at its focus.
(c) The portion of the wavefront of the light from a distant star intercepted by the Earth.
Answer:
(a) Spherical
(b) Plane
(c) Plane

Question 3.
(a) The refractive index of glass is 1.5. What is the speed of light in glass? (Speed of light in a vacuum is 3.0 x 10⁸ ms^-1)
(b) Is the speed of light in glass independent of the colour of light? If not, which of the two colours red and violet travels slower in a glass prism?
Answer:

(b) The speed of light in glass is not independent of the colour (wavelength) of light of the two, violet light travels slower in a glass prism.

Question 4.
In Young’s double-slit experiment, the slits are separated by 0.28 mm and the screen is placed 1.4 m away. The distance between the central bright fringe and the fourth bright fringe is measured to be 1.2 cm. Determine the wavelength of light used in the experiment.
Answer:

Question 5.
In Young’s double-slit experiment using monochromatic light of wavelength A, the intensity of light at a point on the screen where path difference is x, is K What is the intensity of light at a point where path difference is λ /3?
Answer:
When the path difference is λ :
When two light waves of amplitudes a, and a₂ superpose each other at a point, then the intensity of light at that point is given by,
I = a² + a² +a₁a₂ cosφ ………………..(1)
where φ is the phase difference between the two waves.
a₁ = a₂ = a (say), I = K units.
Also, the path difference of λ is equivalent to a phase difference of 2π i e.
φ = 2 π rad= 360°
equation (1) becomes,
K = a² + a² + 2a x a cos 360°
= 2a² + 2a² x 0
a² = k/2   …………………………. (2)

Question 6.
A beam of light consisting of two wavelengths, 650 nm and 520 nm, is used to obtain interference fringes in Young’s double-slit experiment.
(a) Find the distance of the third bright fringe on the screen from the central maximum for wavelength 650 nm.
(b) What is the least distance from the central maximum where the bright fringes due to both the wavelengths coincide?
Answer:
λ = 650nm = 650 x 10^-9m
λ¹ =520nm = 520 x 10^-9m
(a) A distance of n^th bright fringe from the central maximum,
\({ y }_{ n }=\frac { nDx }{ d } \)
∴ The distance of the third bright fringe (n = 3) for wavelength λ(-650 x 10^-9 m),

(b) Suppose that the nth bright fringe due to wavelength X coincides with the nth bright fringe due to wavelength λ¹

Question 7.
In a double-slit experiment, the angular width of a fringe is found to be 0.2° on a screen placed 1 m away. The wavelength of light used is 600 nm. What will be the angular width of the fringe if the entire experimental apparatus is immersed in water? Take the refractive index of water to be 4/3.
Answer:
λ= 600 nm = 600 x 10^-9 m D= lm
The angular width of the fridge,

Question 8.
What is the Brewster angle for air to glass transition? (Refractive index of glass = 1.5.)
Answer:
For air to glass transition,
n = tan i_p where i = Brewster angle
.’. 1.5 = tan i or i_p = tan^-1 1.5 = 56.3°

Question 9.
Light of wavelength 5000 A falls on a plane reflecting surface. What are the wavelength and frequency of the reflected light? For what angle of incidence is the reflected ray normal to the incident ray?
Answer:
X = 5000A = 5 x 10^-7 m
on reflection, no change occurs in wavelength, frequency, and speed of the incident light.
∴ The wavelength of reflected light = 5000Å.
Taking C = 3 x 10⁸ ms^-1. The frequency of reflected light is given by
\(V=\frac { C }{ \lambda } =\frac { 3\times { 10 }^{ 8 } }{ 5\times { 10 }^{ 7 } } =6\times { 10 }^{ 14 }Hz\)
The reflected ray is normal to the incident ray, when the angle of incidence is equal to 45°

Question 10.
Estimate the distance for which ray optics is good approximation for an aperture of 4 mm and wavelength 400 nm.
Answer:
a = 4mm = 4x 10³m
λ = 400nm = 400 x 10^-9 m
\({ Z }_{ r }=\frac { { a }^{ 2 } }{ \lambda } =\frac { (3\times { 10 }^{ -3 })^{ 2 } }{ 400\times { 10 }^{ -9 } } =40m\)

2nd PUC Physics Wave Optics Additional Exercises

Question 11.
The 6563 Å H α line emitted by hydrogen in a star is found to be redshifted by 15 Estimate the speed with which the star is receding from the Earth.
Answer:
x = 6563 A = 6563 x 10^-10 m
ΔX = 15 A = 15 ×10^-10 m
Let V be the speed with which the star is receding from the earth. Then, from Doppler’s effect in light,

The negative sign shows that the star is receding.

Question 12.
Explain how Corpuscular theory predicts the speed of light in a medium, say, water, to be greater than the speed of light in a vacuum. Is the prediction confirmed by experimental determination of the speed of light in water? If not, which alternative picture of light is consistent with the experiment?
Answer:

Suppose that the light corpuscles traveling with a velocity C in the rarer medium along AO strike the interface X Y separating the denser medium (say, water) from a rarer medium as shown in the above figure. After refraction, the light corpuscles travel inside the denser medium along O B with a velocity V. Let i and r be the angles of incidence and reflection respectively.

According to Newton’s corpuscular theory, the light corpuscles experience a force of attraction due to the denser medium, which acts along normal to the interface X Y. Obviously, the component of their velocities before and after the refraction along X Y must remain the same.

medium is greater than that in a rarer medium. This result of the corpuscular theory is against the experimental result and therefore this theory was discarded. On the basis of Huygen’s wave theory, the phenomenon of refraction can be easily explained and it can be proved that c >v. Therefore, the wave picture of light is consistent with the experimental result.

Question 13.
You have learned in the text how Huygens’ principle leads to the laws of reflection and refraction. Use the same principle to deduce directly that a point object placed in front of a plane mirror produces a virtual image whose distance from the mirror is equal to the object distance from the mirror.
Answer:
Consider that a point object O is placed in front of a plane mirror x y and a spherical wavefront APB originating from the object is incident on the mirror as shown in figure

The lines OA, OP and OB (normal to the incident wavefront APB at the points a’ P and B) represent the incident rays. Since the distance OP is smaller than O a’ or OB’ > the disturbance will reach point P earlier than it reaches points a’ and b’ on the mirror.

Therefore, the instant, when the disturbance reaches the points a’ and b’ > the secondary wavelet from the point P will grow into a sphere of radius ((OA’ – OP) or (OB’ – OP). At this instant, the points a’ and b’ on the mirror have just become the sources of secondary wavelets and therefore, the secondary wavelets originating from these points will be ‘of zero radii at that instant.

To find the reflected wavefront (new position of the wavefront after reflection from the plane mirror); with the point P as centre, draw a sphere of radius PP’ = (OA’-OP) or (OB’-OP). Then, the sphere A’ P’ B’, the common envelope of the secondary wavelets issuing out from the points a’, p’ and b’ gives the reflected wavefront (diverging) and the lines IAS IP’ and jb’ normals to the reflected wavefront represent the reflected rays. The point I, from which the reflected wavefront appears to come from, is the virtual image of the object O From simple geometry,
IP = OP i..e, image is formed as for behind the plane mirror as the object is in front of it.

Question 14.
Let us list some of the factors, which could possibly influence the speed of wave propagation:
(i) Nature of the source.
(ii) Direction of propagation.
(iii) Motion of the source and/or observer.
(iv) Wavelength
(iv) Intensity of the wave.
On which of these factors, if any, does
(a) The speed of light in vacuum,
(b) The speed of light in a medium (say, glass or water), depends?
Answer:
(a) Dependence of the speed of light in a vacuum: The speed of light in a vacuum is a universal constant. It is independent of all the factors listed above. It may be pointed out that Newton’s ion relativity principle does not apply to the speed of light. The fact that the speed of light is independent of the relative motion between the source and the observer is one of the postulates of Einstein’s special theory of relativity.

(b) Dependence of the speed of light in a medium:

• It does not depend on the direction of propagation, provided the medium is isotropic.
• It does not depend on the relative motion between the source and the medium. However, it depends on relative emotion between, the source and the observer
• It depends on the wavelength
• It does not depend on the intensity.

Question 15.
For sound waves, the Doppler formula for frequency shift differs slightly between the two situations:
(i) a source at rest; observer moving, and
(ii) source moving; observer at rest. The exact Doppler formulas for the case of light waves in vacuum are, however, strictly identical for these situations. Explain why this should be so. Would you expect the formulas to be strictly identical for the two situations in the case of light travelling in a medium?
Answer:
Doppler effect for sound waves is asymmetric i.e. for the same relative motion in the cases (i) and (ii), the apparent change in the frequency is not the same. It is because sound waves require a medium for their propagation and the motion of the observer relative to the medium is different in two cases.

Doppler effect for light waves is symmetric i.e. for the same relative motion in the case (i) and (ii), the apparent change in the frequency is the same. For light waves in a vacuum, there is no difference in the two cases. It is because the relative motion between the source and the observer is not affected, whether the source is in motion or the observer is in motion. However, for the light waves in a medium, the situations in the two cases are different as in the case of the Doppler effect for sound waves. Likewise, the formulas for the Doppler effect in the two cases will be different.

Question 16.
In a double-slit experiment using the light of wavelength 600 nm, the angular width of a fringe formed on a distant screen is 0.1°. What is the spacing between the two slits?
Answer:

Question 17.
Answer the following questions:

(a) In a single slit diffraction experiment, the width of the slit is made double the original width. How does this affect the size and intensity of the central diffraction band?
(b) In what way is diffraction from each slit related to the interference pattern in a double-slit experiment?
(c) When a tiny circular obstacle is placed in the path of light from a distant source, a bright spot is seen at the centre of the shadow of the obstacle. Explain why?
(d) Two students are separated by a 7 m partition wall in a room 10 m high. If both light and sound waves can bend around obstacles, how is it that the students are unable to see each other even though they can converse easily.
(e) Ray optics is based on the assumption that light travels in a straight line. Diffraction effects (observed when light propagates through small apertures/slits or around small obstacles) disprove this assumption. Yet the ray optics assumption is so commonly used in understanding location and several other properties of images in optical instruments. What is the justification?
Answer:
(a) The width of central maximum
\(\frac { 2D\lambda }{ a } \)
If the width of the slit
(a) is made double of the original, the width of the central diffraction band will reduce to half. The intensity of the central diffraction band coil become four times.

(b) The intensity of interference fringes in young’s double slit experiment is superposed by the diffraction pattern of each slit.

(c) The central bright spot is produced due to the constructive interferences of the waves from the edge of the circular obstacle.

(d) For pronounced diffraction effect, the size of the obstacle should be comparable to the wavelength of the waves. The size of partition is very large as compared to the wavelength of light and hence it is not diffracted and the two students cannot see each other.

(e) In optical instruments, the sizes of the aperture is very large as compared to the wavelength of the light used. As such, the diffraction of light wave is of no significance.

Question 18.
Two towers on top of two hills are 40 km apart. The line joining them passes 50 m above a hill halfway between the towers. What is the longest wavelength of radio waves, which can be sent between the towers without appreciable diffraction effects?
Answer:
The hills will not obstruct the transmitted radio waves, if over the halfway distance (Z_f) between the hills, the spreading of the signal is limited to the distance (a) of the line of sight from the hills.

Question 19.
A parallel beam of light of wavelength 500 nm falls on a narrow slit and the resulting diffraction pattern is observed on a screen 1 m away. It is observed that the first minimum is at a distance of 2.5 mm from the centre of the screen. Find the width of the slit.
Answer:
λ= 500nm = 500 x 10^-9m
D = 1m
The distance of first minimum from the centre of the screen,

Question 20.
Answer the following questions:

(a) When a low flying aircraft passes
overhead, we sometimes notice a slight shaking of the picture on our TV screen. Suggest a possible explanation.

(b) As you have learnt in the text, the principle of linear superposition of wave displacement is basic to understanding intensity distributions in diffraction and interference patterns. What is the justification of this principle?
Answer:
(a) A low flying aircraft reflects the TV signal. Due to interference between the direct signal and the reflected signal, the picture on TV screen shows a slight shaking.

(b) A wave equation can be expressed as a differential equation. The super position principle follows from the linear character of the wave equation. If y₁ and y₂ are the solutions of the wave equation, then their any linear combination is also the solution of the wave equation.

Question 21.
In deriving the single slit diffraction pattern, it was stated that the intensity is zero at angles of n%/a. Justify this by suitably dividing the slit to bring out the cancellation.
Answer:
Divide the slit of width an into n parts, so that the width of each small part of the slit is

For a path difference nλ between the waves from two extreme ends of the slit,
\(\theta =\frac { n\lambda }{ a } =\frac { n\lambda }{ n{ a }^{ \prime } } =\frac { \lambda }{ { a }^{ \prime } } \)
Each of the n parts of the slit will send zero intensity in the direction 0. Obviously, all the n parts together will also give zero intensity.

2nd PUC Physics Wave Optics Additional Questions and Answers

Question 1.
Two coherent sources, whose intensity ratio is 10: 1 produce interference fringes. Calculate the ratio of intensity of maxima and minima in the fringe system.
Answer:

Question 2.
In young’s double slit experiment, the two slits are 0.5 mm apart. The screen is placed lm away from the slits. The distance of 11^th fringe from the first fringe is 1 cm. Calculate the wavelength of light used.
Answer:
The distance of the 11^th fringe from the first fringe is equal to width of 10 fringes.

Question 3.
Determine the angular separation between central maximum and first order maximum of the diffraction pattern due to a single slit of width 0.25mm, when light of wavelength 5890 Å is incident on it normally.
Answer:

Question 4.
Two spectral lines of sodium D₁ and D₂ have wavelengths of approximately 5,890 and 5896 Å sodium lamp sends incident plane wave on a slit of width 2 x 10⁶ m. A screen is located 2m from the slit. Find the spacing between the first maxima of two sodium lines as measured on the screen.
Answer:
The distance of first secondary maxima from the centre of screen,

Question 5.
Colours appear on a thin soap film and soap bubbles due to the phenomenon of
(A) interference
(B) scattering
(C) diffraction
(D) dispersion
Answer:
(A) interference

Question 6.
The frequency of an e.m. wave which is best suited to observe a particle of radius
3 x 10^-6  m, is of order of
(A) 10¹⁵
(B) 10¹³
(C) 10¹⁴
(D) 10¹²
Answer:
The particle can be observed when wavelength of light used is of the order of its size. Therefore, required frequency

Question 7.
Golden view of sea shell is due to
(A) diffraction
(B) dispersion
(C) polarisation
(D) reflection
Answer:
(C) polarisation

Question 8.
In a young’s experiment, two coherent sources are placed 0.9mm apart and the fringes are observed lm away. If it produces the second dark fringe at a distance of 1mm from the central fringe, the wavelength of monochromatic light used would be
(A) 60 x 10^-4cm
(B) 10 x 10^-4 cm
(C)10 x 10^-5cm
(D) 6 x 10^-5cm
Answer:

Question 9.
For the relaxed eye, the magnifying power of microscope is.

Answer:
(A)

Question 10.
In a Fresnel biprism experiment, the two positions of lens give separation between the slits as 16cm and 9cm respectively. What is the actual distance of separation?
(A) 12.5cm
(B) 12cm
(C) 13cm
(D) 14cm
Answer: (B)
The actual distance of separation between the slits,
\(d=\sqrt { { d }_{ 1 }{ d }_{ 2 } } =\sqrt { 16\times 9 } =12cm\)

You can Download Chapter 8 Electromagnetic Waves Questions and Answers, Notes, 2nd PUC Physics Question Bank with Answers, Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.

Karnataka 2nd PUC Physics Question Bank Chapter 8 Electromagnetic Waves

2nd PUC Physics Electromagnetic Waves NCERT Text Book Questions and Answers

Question 1.
Figure 8.6 shows a capacitor made of two circular plates each of radius 12 cm, and separated by 5.0 cm. The capacitor is being charged by an external source (not shown in the figure). The charging current is constant and equal to 0.15A.
(a) Calculate the capacitance and the rate of charge of potential difference between the plates.
(b) Obtain the displacement current across the plates.
(c) Is Kirchhoff’s first rule (junction rule) valid at each plate of the capacitor? Explain.

Answer:

(c) Yes, Kirchhoff’s first law will be valid at each plate of the capacitor, provided the electric current means the sum of the conduction and the displacement currents.

Question 2.
A parallel plate capacitor (Fig. 8.7) made of circular plates each of radius R = 6.0 cm has a capacitance C = 100 pF. The capacitor is connected to a 230 Y ac supply with an (angular) frequency of 300 rad s¹.
(a) What is the rms value of the conduction current?
(b) Is the conduction current equal to the displacement current?
(c) Determine the amplitude of B at a point 0 cm from the axis between the plates.

Answer:

(b) Yes the conduction current and the displacement current will be equal. It is true, even if the conduction current is oscillating.
(c) Let us first derive an expression for the amplitude of the magnetic field at a distance x from the axis of the capacitor. To do so, place a circular loop of radius r between the two plates of the capacitor with its face parallel to the plates and its centre on the axis of the plates.
According to modified Ampere’s circuital law,

The amplitude of the magnetic field at a distance r from the axis of the plates is then, given by.

Question 3.
What physical quantity is the same for X- rays of wavelength 10^-1 m, the red light of wavelength 6800 A, and radio waves of wavelength 500m?
Answer:
All e.m. waves travel with the same speed c = 3 x 10⁸ m s^-1 in a vacuum.
Therefore, X-rays, red light, and radio waves have the same speed.

Question 4.
A plane electromagnetic wave travels in a vacuum along the z-direction. What can you say about the directions of its electric and magnetic field vectors? If the frequency of the wave is 30 MHz, what is its wavelength?
Answer:
The electric and magnetic field vectors are in X Y – plane,

Question 5.
A radio can tune in to any station in the 7.5 MHz to 12 MHz bands. What is the corresponding wavelength band?
Answer:
Corresponding to v = 7.5 MHz = 7.5 × 10⁶Hz

Question 6.
A charged particle oscillates about its mean equilibrium position with a frequency of 10⁹. What is the frequency of the electromagnetic waves produced by the oscillator?
Answer:
The frequency of the produced E.M. wave is the same as the frequency of oscillating charged particles i. e. 10⁹ Hz.

Question 7.
The amplitude of the magnetic field part of a harmonic electromagnetic wave in a vacuum is B_o = 510 nT. What is the amplitude of the electric field part of the wave?
Answer:
B₀ = 510 nT = 510 x 10^-9T
The amplitude of the electric field part of the wave,
E₀ =CB₀ =3 x l0⁸ x 510 x l0^-9 =153NC^-4

Question 8.
Suppose that the electric field amplitude of an electromagnetic wave is E₀ = 120 N/ C and that its frequency is v = 50.0 MHz.
(a) Determine, B_0,ω, k, and λ,
(b) Find expressions for E and B.
Answer:

Question 9.
The terminology of different parts of the electromagnetic spectrum is given in the text. Use the formula E = hv (for energy of a quantum of radiation: photon) and obtain the photon energy in units of eV for different parts of the electromagnetic spectrum. In what way are the different scales of photon energies that you obtain related to the sources of electromagnetic radiation?
Answer:

Question 10.
In a plane electromagnetic wave, the electric field oscillates sinusoidally at a frequency of 2.0 x 10¹⁰ Hz and amplitude 48 V m^-1.
(a) What is the wavelength of the wave?
(b) What is the amplitude of the oscillating magnetic field?
(c) Show that the average energy density of the E field equals the average energy density of the B field, [c = 3 x 10⁸ ms^-1]
Answer:
u =2 x 10¹⁰Hz
E₀ = 48 Vm⁴ C
= 3 x l0⁸ms^-1

Question 11.
Suppose that the electric field part of an electromagnetic wave in a vacuum is E= {(3.1 N/C) cos [(1.8 rad/m) y + (5.4 x 10⁶ rad/s)t]} \(\hat { i } \)

• What is the direction of propagation?
• What is the wavelength λ?
• What is the frequency V?
• What is the amplitude of the magnetic field part of the wave?
• Write an expression for the magnetic field part of the wave.

Answer:
The electric field part of the electromagnetic wave is given by,
\(\vec { E } \) = (3.1 NC^-1 ) cos [(1,8 rad m^-1) y + (5.4x 10⁶ rad s¹) t]\(\hat { i } \) it follows that
E₀ = 3.1 NC^-1
k =1.8 rad m^-1
ω = 5.4×10⁶ rad s^-1
(a) Since the argument of since in the expression for electric field is of type (ky +cot), the direction of propagation of the electromagnetic wave is along the negative Y-axis.

(b) The wavelength of the wave,

(e) The electric field and the direction of propagation of the e.m. wave are along negative X-axis and negative Y-axis respectively. Therefore, the magnetic field is along negative Z-axis and expression for it is given by
B = (10.33nT) cos [(1.8 rad m^-1) y + (5.4 x 10⁶rad s^-1)t] \(\hat { k } \)

Question 12.
About 5% of the power of a 100 W light bulb is converted to visible radiation. What is the average intensity of visible radiation
(a) At a distance of lm from the bulb?
(b) At a distance of 10 m? Assume that the radiation is emitted isotropically and neglect reflection.
Answer:
P = 100 W
n = 5%
Since the efficiency of the bulb is 5%, the effective power of the bulb.
\({ P }_{ eff }=p\times n=100\times \frac { 5 }{ 100 } =5w\)
At a distance, ‘r’ the radiation coming from the bulb is distributed over the surface of a sphere of radius r i.e. over an area.
A = 4πr²
Therefore, the intensity of light at a distance of r,

Question 13.
Use the formula λ_mT = 29 cm K to obtain the characteristic temperature ranges for different parts of the electromagnetic spectrum. What do the numbers that you obtain tell you?
Answer:

These numbers tell us the order of temperature for obtaining radiations in different parts of the electromagnetic spectrum. At these temperatures, the radiation of the corresponding wavelength in a particular case can be emitted at a lower temperature also, but its intensity will not be maximum.

Question 14.
Given below are some famous numbers associated with electromagnetic radiations in different contexts in physics. State the part of the electromagnetic spectrum to which each belongs.
(a) 21 cm (wavelength emitted by atomic hydrogen in interstellar space).
(b) 1057 MHz (frequency of radiation arising from two close energy levels in hydrogen; known as Lamb shift).
(c) 7 K [temperature associated with the isotropic radiation fHifag nil space-thought to be a relic of the big-bang origin of the universe}.
(d) 5890 A – 5890 A (double lines of sodium}
(e) 14.4 keV {energy of a particular transition in ⁵⁷Fe nucleus associated with a famous high-resolution spectroscopic method (Mossbauer spectroscopy)].
Answer:
(a) Given wavelength is of the order of 10^-2 m i.e. short radio wave.
(b) Frequency is of the order of 10⁹ Hz e. short radio wave.
(c) Microwave
(d) Visible(Yellow)
(e) X-rays (or soft γ-rays) region

Question 15.
Answer the following questions:

1. Long-distance radio broadcasts use short-wave bands. Why?
2. It is necessary to use. satellites for long-distance TV transmission. Why?
3. Optical and radio telescopes are built on the ground but X-ray astronomy is possible only from satellites orbiting the earth. Why?
4. The small ozone layer on top of the stratosphere is crucial for human survival. Why?
5. If the earth did not have an atmosphere, would its average surface temperature be higher or lower than what it is now?
6. Some scientists have predicted that a global nuclear war on the earth would be followed by a severe nuclear winter’ with a devastating effect on life on earth. What might be the basis of this prediction?

Answer:

1. Long-distance radio broadcasts make use of sky waves. The ionosphere of the earth’s atmosphere reflects the radiations of this range.
2. For very long-distance TV transmission, a very high frequency is required. Waves of this frequency just pass through the ionosphere and are not reflected back. Therefore, a satellite is required to reflect the signals to the earth.
3. The atmosphere of the earth can absorb X-rays but visible waves and radio waves pass through it.
4. The ozone layer absorbs ultraviolet (UV) radiation emitted by the sun and prevents them to reach the earth. Ultraviolet radiations are harmful for the life on earth.
5. In this case, there will be no greenhouse effect. So the earth will be at a low temperature in the absence of the atmosphere.
6. In the case of worldwide nuclear war, the sky may get overcast with clouds of nuclear radiation. These clouds will stop the passage of sunlight to earth. Thus, the earth will be as cool as in winter.

2nd PUC Physics Electromagnetic Waves Additional Questions and Answers

Question 1.
What is Maxwell’s displacement current?
Answer:
The displacement current is produced, when in an electric circuit (say across the plates of a charged capacitor), the electric field changes with time. Mathematically,

Question 2.
Can an electromagnetic wave be deflected by a magnetic or electric field? Explain.
Answer:
No, an electromagnetic wave cannot be deflected by a magnetic or electric field. It is because they do not consist of charged particles. They merely propagate in the form of electric and magnetic fields varying both in space and time.

Question 3.
The dimensions of \(\frac { 1 }{ { \mu }_{ 0 }{ \in }_{ 0 } } \) where symbols have their usual meanings are:
(A) [L¹ T]
(B) [L² T²]
(C) [L² T^-2]
(D) [L T¹]
Answer:
The velocity of the electromagnetic wave in free space

Question 4.
Which of the following are not electromagnetic waves
(A) Cosmic rays
(B) γ-rays
(C) β – rays
(D) X-rays
Answer:
(C) β – rays

Question 5.
If \({ \in }_{ 0 }\) and \({ \mu }_{ 0 }\) are the electric permeability and magnetic permeability in free space, ∈ and µ are the corresponding quantities in a medium, then index of refraction of the medium is

Answer:
The velocity of the electromagnetic waves in free space is given by

Question 6.
The speed of electromagnetic waves is independent of
(A) Wavelength
(B) Frequencies
(C) Intensity
(D) Medium in which it travels
Answer:
(C) Intensity

Question 7.
If an electromagnetic wave propagating through vacuum is described by,
E = E₀ sin (Kx – wt); B = B₀ sin (Kx -ωt) then,
(A) E₀K = Boω
(B) E₀B₀ = ωK
(C) E₀ω=B₀K
(D) E₀B₀=ω/K
Answer:
(A) E₀K = Boω

Question 8.
The oscillating magnetic field in a plane electromagnetic wave is given by
B_y = 8×10⁶sin [2 × 10^-6t + 300 πx] (int) calculate the wavelength of the wave
Answer:

Question 9.
Find the wavelength of the electromagnetic wave of frequency 5x 10¹⁹ Hz in free space. Identify the wave.
Answer:

Question 10.
Give the ratio of velocities of light rays of wavelength 4000 A in a vacuum.
Answer:
The velocity of light rays of different wavelengths in a vacuum is the same and hence the ratio of their velocities is 1.

You can Download Chapter 9 Ray Optics and Optical Instruments Questions and Answers, Notes, 2nd PUC Physics Question Bank with Answers, Karnataka State Board Solutions help you to revise the complete Syllabus and score more marks in your examinations.

Karnataka 2nd PUC Physics Question Bank Chapter 9 Ray Optics and Optical Instruments

2nd PUC Physics Ray Optics and Optical Instruments NCERT Text Book Questions and Answers

Question 1.
A small candle, 2.5 cm in size is placed at 27 cm in front of a concave mirror of radius of curvature of 36 cm. At what distance from the mirror should a screen be placed in order to obtain a sharp image? Describe the nature and size of the image. If the candle is moved closer to the mirror, how would the screen have to be moved?
Answer:

Therefore, the screen should be placed at a distance of 54cm from the mirror on the same side as the object,

When the candle is moved closer to the mirror, the image will move away from the mirror and likewise, the screen has to be moved away to bring the image on the screen. However, when the candle is at a distance of less than 18 cm, the image formed will be virtual. In that situation, the image cannot be brought to the screen.

Question 2.
A 4.5 cm needle is placed 12 cm away from a convex mirror of focal length 15 cm. Give the location of the image and the magnification. Describe what happens as the needle is moved farther from the mirror.
Answer:

When the needle is moved farther from the mirror, the image also moves away from the mirror but will not go beyond the focus of the mirror.

Question 3.
A tank is filled with water to a height of 12.5 cm. The apparent depth of a needle lying at the bottom of the tank is measured by a microscope to be 9.4 cm. What is the refractive index of water? If water is replaced by a liquid of refractive index 1.63 up to the same height, by what distance would the microscope have to be moved to focus on the needle again?
Answer:
When the tank is filled with water:
Real depth = 12.5cm
Apparent depth = 9.4cm

Therefore objective and eyepiece should be placed at 11,67cm apart and the object at a distance of 1,5cm from the objective.

Question 4.
A small telescope has an objective lens of a focal length of 140 cm and an eyepiece of a focal length of 5.0 cm. What is the magnifying power of the telescope for viewing distant objects when
(a) the telescope is in normal adjustment (i.e., when the final image is at infinity)?
(b) the final image is formed at the least distance of distinct vision (25cm)?
Answer:
Here, f₀ = 140cm, f_e = 5.0cm
(a) When the telescope is in normal adjustment,

(b) When the image is formed at least distance of distinct vision, then

Question 5.
(a) For the telescope described in Exercise 9.34 (a), what is the separation between the objective lens and the eyepiece?
(b) If this telescope is used to view a 100 m tall tower 3 km away, what is the height of the image of the tower formed by the objective lens?
(c) What is the height of the final image of the tower if it is formed at 25cm?
Answer:
Here, f₀ = 140cm; f_e = 5.0cm
(a) The separation between the objective and the eye-piece,
L = f + f = 140 + 5 = 145 cm
(b) Let a be the angle formed by the object at the objective lens. Then,

Let A’ B’ be the height of the image produced by the objective lens at its focus. From the figure, it follows that the angle formed by the image a’ g’ at the objective lens is also equal to a.

Question 6.
A Cassegrain telescope uses two mirrors as shown in Fig. 9.33. Such a telescope is built with mirrors 20mm apart. If the radius of curvature of the large mirror is 220mm and the small mirror is 140mm, where will the final image of an object at infinity be?
Answer:

When the object lies at infinity, the concave mirror will form the image of the object at its focus. As this image lies behind the convex mirror, it acts as a virtual object for the convex mirror.

Question 7.
Light incident normally on a plane mirror attached to a galvanometer coil retraces backward as shown in Fig. 9.36. A current in the coil produces a deflection of 3.5o of the mirror. What is the displacement of the reflected spot of light on a screen placed 1.5 m away?

Answer:

When a plane mirror rotates through a certain angle, the reflected ray turns twice the angle of rotation. Therefore, the angle between the incident ray AO and the reflected ray is,

Question 8.
Figure 9.37 shows a biconvex lens (of refractive index 1.50) in contact with a liquid layer on top of a plane mirror. A small needle with its tip on the principal axis is moved along the axis until its inverted image is found at the position of the needle. The distance of the needle from the lens is measured to be 45.0cm. The liquid is removed and the experiment is repeated. The new distance is measured to be 30.0cm. What is the refractive index of the liquid?
Answer:

The liquid between the convex lens and the plane mirror behaves as a plano-concave lens. Let f₁ and f₂ be the focal length of the convex lens and the liquid plano-concave lens. In the arrangement as shown in. Figure (b) as the needle and its image coincide with each other, the rays of light retrace their path. Therefore, the rays of light after refraction through the lens are falling normally on the plane mirror. It can happen so if the needle lies at the focus of the convex lens. Hence, f, = 30cm From the lens maker’s formula, we have

In the arrangement as shown in Figure (a). As discussed above, now the needle lies at the focus of the combination of the two lenses. If F is the focal length of the combination of the two lenses, then

2nd PUC Physics Ray Optics and Optical Instruments Additional Questions and Answers

Question 1.
Why is that sun-glasses (gaggles), which has curved surface, do not have any power?
Answer:
The two surfaces of the goggle lens are parallel i.e. possess the same radii of curvature. Since one surface is convex and other equally concave, the powers of the two surface is equal but of opposite signs. The total power of the goggle lens (p’) is the algebraic sum of the powers of the individual surfaces
p’ =p₁ +p₂ =p+(-p) = 0

Question 2.
An illuminated object and a screen are placed 90 cm apart. Determine the focal length and nature of the lens required to produce a clear image on the screen, twice the size of the object.
Answer:
Since the image is formed on the screen, it is a real image. Let the distance of the object from the lens be x. Then, distance of the image from the lens be (90-x)

Question 3.
Two lenses of power + 15D and -5D are in contact with each other forming a combination lens,
(a) what is the focal length of this combination?
(b) An object of size 3cm is placed at 30cm from this combination of lenses. Calculate the position and size of the image formed.
Answer:
(a) Power of the combination,
P = P₁ + P₂= 15 +(-5)= 10D
Therefore, focal length of the combination,

Question 4.
A glass prism has a minimum angle of deviation of 5 in the air. State with reason, how the angle of minimum deviation will change if the prism is immersed in a liquid of refractive index greater than 1.
Answer:
We know that for a glass prism placed in the air,

when the prism is immersed in a liquid of refractive index greater than 1, its refractive index w.r.t liquid will become less than p. From the above relation, it follows that the angle of minimum deviation will decrease.

Question 5.
Which of the following is used in optical fibres?
(A) Total internal reflection
(B) Scattering
(C) Diffraction
(D) Refraction
Answer:
(A) Total internal reflection

Question 6.
An astronomical telescope has a large aperture to:
(A) Reduce spherical aberration
(B) Have high resolution
(C) Increase span of observation
(D) Have low dispersion.
Answer:
(B) Have high resolution
The resolving power of the telescope is given by
\(R.P=\frac { D }{ 1.22\lambda } \)
∴ The resolving power of the telescope will be high, its objective is of a large aperture.

Question 7.
The refractive index of the material of an equilateral prism is \(\sqrt { 3 } \). What is the angle of minimum deviation?
(A) 45°
(B) 60″
(C) 37°
(D) 30°
Answer:

Question 8.
Greenlight of wavelength 5460 is incident on an air-glass interface. If the refractive index of glass is 1.5, the wavelength of light in glass would be
(A) 3,640 Å
(B) 5460 Å
(C) 4861 Å
(D) None of the above
Answer:

Question 9.
A light wave of frequency V and wavelength X travels from air to glass. Then,
(A) V changes
(B) x does not change
(C) V does not change, X changes
(D) V and X changes
Answer:
(C) V does not change, X changes

Question 10.
Two mirrors are kept at 60° to each other and a body is placed at the middle. Total number of images formed is
(A) six
(B) four
(C) five
(D) three
Answer:

(C) five

Question 11.
Two thin lenses of power +5D and -3D are in contact. What is the focal length of the combination (CBSE 2001)
Answer:

Question 12.
A glass lens of refractive index 1.5 is kept in a liquid. What must be the refractive index of the liquid so that the lens will disappear  (CBSE 2008)
Answer:
To disappear the lens the refractive index of liquid should be the same i.e. 1.5.

Question 13.
For which wavelength is an eye the most sensitive.
Answer:
5500 A

Question 14.
Use mirror formula to show that for an object lying between the pole and the focus of a conceive mirror, the image formed is always virtual for a concave mirror (CBSE 2008)
Answer:
f is negative and u is negative
Since object lying between the pole and focus u < f

Question 15.
Using the Lens formula, show that a concave Lens produces a virtual and diminished image independent of the location of the object. (KU – 2009)
Answer:

magnification is less than 1 hence image is virtual and diminished

Question 16.
What should be the position of the object relative to the biconvex lens so that it behaves like a magnifying glasses.
Answer:
If an object is kept between the optical centre and the focus of the biconvex lens, then the lens behaves like a magnifying glass.

You can Download Chapter 8 National Income Accounting Questions and Answers, Notes, 2nd PUC Economics Question Bank with Answers Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.

Karnataka 2nd PUC Economics Question Bank Chapter 8 National Income Accounting

2nd PUC Economics National Income accounting One Mark Questions and Answers

Question 1.
Write the meaning of national income.
Answer:
National Income refers to the money value of all the final goods and services produced in an economy within an accounting year. It also includes the income from abroad factor.

Question 2.
What are final goods?
Answer:
The final goods are those goods which are purchased for final utility or usage.

Question 3.
What do you mean by intermediate goods?
Answer:
The intermediate goods are those goods which are produced by one producer and used by another producer as a semi finished goods to produce some other final goods.

Question 4.
How do you get NDP?
Answer:
NDP is obtained by deducting depreciation cost from Gross Domestic Product (GDP) .

Question 5.
What is Per capita income?
Answer:
The per capita income is the average income of the population which is calculated by dividing the national income by the total population.

Question 6.
What is economic welfare?
Answer:
Economic welfare is the satisfaction derived by an individual from the use of economic goods and services.

Question 7.
What are externalities?
Answer:
Externalities are those which are unintentional consequences of an economic action of a firm that accrue to another firm.

Question 8.
What are Transfer Payments?
Answer:
The payments made by the Government like old age pension, widow pension, scholarships etc. are called transfer payments.

2nd PUC Economics National Income accounting Two Marks Questions and Answers

Question 1.
What are the differences between final goods and intermediate goods?
Answer:

Final Goods	Intermediate Goods
(i) Final goods are those goods which are purchased for final utility or usage.	(i) Intermediate goods are those goods which are produced by one producer and used by another producer to produce some other final goods
(ii) Example for final goods are TV, mobile, sugar, car, shoes etc.	(ii) Examples are raw cotton, wood etc.

Question 2.
Differentiate between consumer goods and capital goods with examples.
Answer:

Consumer Goods	Capital Goods
(i) These are the goods which are purchased for consumption.	(i) These are the goods which are used to produce other products.
(ii) Example food, clothes, TV, mobile, sugar, car, shoes etc.	(ii) Examples are machinery, tools, roads.

Question 3.
Between net investment and capital, which is stock and which is a flow.
Answer:
Between net investment and capital, net investment is stock and capital is a flow.

Question 4.
Write the meaning of circular flow of income.
Answer:
The circular flow of income illustrates the process where by the national income of an economy flows in a circular manner continuously between different sectors.

Question 5.
Classify the following into stocks and flows: Bank deposits, salary, wealth, food grain stock, exports, imports, foreign exchange reserves, national income.
Answer:

Stocks	Flows
Bank deposits, wealth, food grain stock, foreign exchange reserves.	Salary, exports, imports, national income.

Question 6.
Name the factors of production.
Answer:
There are four factors of production viz.. Land, Labour, Capital and Organisation.

Question 7.
Name the factor payments.
Answer:
The factor payments are Rent, Wages, Interest and Profit.

Question 8.
How does GNP differ from GDP?
Answer:
Gross Domestic Product Gross National Product

Gross Domestic Product	Gross National Product
It is the aggregate value of final goods and services produced within the country during a year. It is a narrow concept.	It is the aggregate money value of all final goods and services produced by a country including income from abroad. It is wider concept

Question 9.
Differentiate between nominal national income and real national income.
Answer:

Nominal National Income	Real National Income
When it is expressed in current prices, it is called nominal income. It does not give a clear picture of the condition of the economy.	It is expressed in terms of base year prices/constant prices. It provides a clear picture of the condition of the economy.

Question 10.
Mention the methods of measuring National Income.
Answer:
There are three methods of measuring national income viz.,

1. Income Method
2. Expenditure Method and
3. Product method.

Question 11.
What is the opinion of the International Monetary Fund (IMF) with regard to income from Foreign firms?
Answer:
The IMF is of the opinion that the income of a foreign firm should be included in the income of the country where it is located. But, profits earned by foreign firms should be credited to the parent country.

Question 12.
Nishanth is a lecturer in a College. He teaches his children at home. Are both teachings included in national income measurement? If not, why?
Answer:

• Nishanth is a lecturer in a College. He gets his salary for his work. The salary is included in the national income.
• Nishanth teaches his children at home. Here, he does not earn any income. So, it is not included in National Income.

Question 13.
What are externalities? Explain with an example.
Answer:
Externalities are those which are unintentional consequences of an economic action of a firm that accrue to another firm. For example, if there is establishment of an atomic power plant, it solves power crisis. It is a positive externality. But, the pollution caused by the power plant is harmful externality.

Question 14.
GDP is not a true indicator of welfare. Give reasons.
Answer:
Hie National income is not a reliable index of economic welfare because of the following reasons.

a) Inequality in the distribution of income.
b) Existence of non-monetary exchanges.
c) GDP does not consider whether the goods produced are useful or harmful.
d) GDP does not consider the manner of production.

Question 15.
What is simple economy?
Answer:
A simple economy is a clased economy in which there is no government or external trade or savings.

Question 16.
Mention any four difficulties in measuring National Income.
Answer:

1. Neglect of transfer payments.
2. Lack of reliable data.
3. Income from illegal activities.
4. Problem of double counting.

2nd PUC Economics National Income accounting Five Marks Questions and Answers

Question 1.
Describe circular flow of income in a simple economy.
Answer:
Circular flow of income illustrates the process whereby the national income of an economy flows in a circular manner continuously between different sectors.

Now let us discuss about a circular flow of income in a simple economy.
A simple economy is a closed economy in which there is no Government or external trade or savings. A simple two-sector model economy is based on the following assumptions:

a) Existence of two sectors viz., household sector and producers.
b) Households are the owners of the factors of production.
c) Households receive income by selling the factor services.
d) There are no savings.
e) The firms produce entire produce to the households.
f) The economy is a closed economic system.

In the above diagram, the household sector provides factors of production to the producers. The firms supply goods and services to the households. It is showtn in outer circle flow and is called real flow. The firms make factor payments like rent, wages, interest and profit to households as reward for factors of production. Households spend this income on buying goods and services. This is money is flow, which is shown in inner circle. In this way, production generates factor income, which is converted into expenditure.

The national income is calculated at three points as per the above chart viz., A, B, C. At point A, national income is calculated by adding all the factor payments and it is called income method. At point B, we take total expenditure incurred by the households on goods and services to calculate national income and it is called expenditure method. At point C, we measure the aggregate value of all the final goods and services produced by all the firms to calculate national income and it is called product method.

Question 2.
Explain macroeconomic-identities GDP, NDP, GNP and NNP.
Answer:
a) Gross Domestic Product(GDP): GDP is the aggregate of the final goods and services produced in the domestic territory of a country during an accounting year.

b) Net Domestic Product ( NP): NDP refers to the market value of all final goods and services turned out in an economy during a given period of time after making allowance for depreciation charges. lt is obtained by subtracting depreciation from GDP.
NDP = GDP – Depreciation.

In simple words we can say that NDP is the net market value of final goods and services produced by its residents and non-residents within the domestic territory of a country in a year.

c) Gross National Product (GNP): It is the most important concept in N.I accounting. It is a National concept. GNP is defined as the total market value of all final goods and services produced in a country in a year’s time.

No allowance for wear and tear cost i.e., depreciation is made. While calculating the GNP, the money value of only the goods and services which are finally consumed by the people are to be taken into account. Hence, the value of all intermediary goods and inputs are to be excluded in order to avoid double or multiple counting.

The income received from foreign investment and from other factor services rendered abroad should be added to the gross domestic product of a country. Similarly, the income generated by the foreigner in a given country should be deducted from the GDP for the purpose of computing the GNP.

GNP = GDP + X – M

X= income earned by nationals abroad .
M= Income earned by foreigners in the given country.

GNP includes:

• The value of all consumption goods which are currently produced.
• The value of all capital goods currently produced.
• Total government expenditure on buying various goods and services.
• Net export value.
• Net amount earned abroad.

GNP = (C+I+G) + (X-M) + (R-P)

d) Net National Product (NNP):
Net national product is the market value of the net output of final goods and services produced by the country during the relevant income period.
NNP = GNP – Depreciation.

Question 3.
Write a note on nominal national income and real national income.
Answer:
Nominal National Income: When the national income is expressed in the prices prevailing , in the year in which it is calculated it is called nominal national income. For example, if the national income of the year 2014 – 15 is calculated as per the prices of 2014-15, it becomes nominal national income.

Defects of Nominal National Income:

• Nominal national Income does not give a clear picture of an economy. If there is rise in prices of goods and services due to scarcity, the nominal national income shows growth in GDP. But it is not true.
• Difficulty in monitoring the changes in the price of all the goods and services.
• Existence of non-monetary transaction hinders in the correct calculation of national income.

Real National Income: As the nominal national income does not provide correct picture of an economy, the concept of real national income is developed. The real national income is expressed in terms of base year prices. While calculating National income, a particular year is taken as base year. The price level is assumed to be as 100 for the base year. The formula to calculate real national income is as follows:

4. Describe any five problems in the measurement of national income.
Answer:
a) Problem of double counting: The greatest difficulty in calculating the national income is that of double counting, which arises from the failure to distinguish properly between a final and an intermediate product. There always exists the fear of a good or a service being included more than once. If it so happens, the national income would work out to be many times the actual.

b) Illegal activities: Income earned through illegal activities such as gambling, illegal extraction of wine, hoarding and black marketing is not included in national income. While calculating national income, such earnings are left out, so the national income works out to less than the actual.

c) Change in price: Another difficulty in calculating national income is that of price changes which fail to keep stable the measuring rod of money for national income. When the price level in the country rises, the national income also shows an increase even though the production might have fallen and vice versa. Thus due to price-changes the national income cannot be adequately measured.

d) Illiteracy: In developing countries, we find crores of people as illiterates. They do not keep proper accounts about the production and sales of their products. Under such circumstances, the estimates of production and earned incomes are simply a guess work.

e) Non-availability of Data: Adequate and correct production and cost data are not available. The data relating to crops, forestry, fisheries, animal husbandry and the activities of petty shop keepers, small enterprises, etc., are not counted. For estimating national income by the income method, data on unearned incomes and on persons employed in the service sector are not available.

Question 5.
Explain the relationship between national income and welfare.
Answer:
Alfred Marshall, Prof.A.C Pigou and J.R.Hicks say that there is a close relationship between economic welfare and national income, because both of them are measures in terms of money. When National income increases, total welfare also increases and vice versa.

The effect of national income on economic welfare can be studied in two ways:

• By change in the size of national income.
• By change in the distribution of National income.

i) The change in the size of National Income: The positive change in the national income increases its volume. As a result people consume more of goods and services, which leads to increase in the economic welfare. Whereas the negative change in national income, results in reduction of its volume. People get lesser goods and services for consumption which leads to decrease in economic welfare.

ii) The change in the distribution of National Income: The distribution of national income takes place in two ways, firstly, by transferring wealth from poor to rich and secondly from the rich to the poor. But, it is advisable to follow the second way in distribution of national income.

The actual relation between the distribution of national income and economic welfare concerns the transfer of wealth flow from the rich to the poor. The redistribution of wealth in favour of the poor is brought about by reducing the wealth of the rich and increasing the income of the poor.

Thus, the increase in national income leads to increase in economic welfare provided that the income of the poor increases instead of decreasing and they improve their standard of living and that the income of the rich decreases in such a way that their productive capacity, investment and capital accumulation do not decline.

Question 6.
“GDP is not a barometer of economic welfare but only a rough indicator”. Analyse this statement.
Answer:
The GDP is not a satisfactory measure of economic welfare because the estimates of national income do not include certain services and production activities which affect welfare. Following are the factors which affect human welfare but not included in GDP estimates:
i) Non-market transactions: Some of the non-market transactions increase welfare but they are not included in national income estimates. The services of housewives within the home and community activities like welfare activities of NGOs influence the welfare of the people but they are not included in GDP.

ii) Consumption of harmful goods: The consumption of harmful goods like cigarettes, liquor, narcotic drugs etc may not bring welfare to the community but they are included in the GDP estimates.

iii) Unequal distribution of National Income: The increase in National Income may not always coincide with the increase in economic welfare of a country. This is mainly because of unequal distribution of income. The rich people may be having more share than the poor.

iv) Environmental concerns: The rapid industrialization and urbanization are causing a severe threat to environment. Many hazardous pollutants are being added to the atmosphere in the name of development which is not in favour of economic welfare. But these are included in GDP estimates.

v) Externalities: An externality is a cost or benefit conferred upon second or third parties as a result of acts of individual production and consumption. But the cost or benefit of an externality cannot be measured in money, terms because it is not included in market activities. For example, the pleasure one gets from his neighbour’s garden is an external benefit and external cost is environmental pollution caused by industries. Both are excluded from national income estimates.

vi) Leisure and work: One of the important things that affect the welfare of a society is leisure. But is not included in GDP. For example, longer working hours may make people unhappy because their leisure is reduced. On the contrary, shorter working hours per week may increase leisure and make people happy.

vii) Manner of production: The economic welfare also depends on the manner of production of goods and services. If goods are produced by child labour or by exploitation of workers, then the economic welfare cannot increase.

Keeping the above limitations in view, GDP cannot be used as a barometer of economic welfare.

2nd PUC Economics National Income accounting Ten Marks Questions and Answers

Question 1.
Explain the difficulties in the measurement of National income.
Answer:
i) Problem of double counting: The greatest difficulty in calculating the national income is of double counting, which arises from the failure to distinguish properly between a final and an intermediate product. There always exists the fear of a good or a service being included more than once. If it so happens, the national income would work out to be many times the actual.

ii) Illegal activities: Income earned through illegal activities such as gambling, illegal extraction of wine, hoarding and black marketing is not included in national income. While calculating national income, such earnings are left out, so the national income works out to less than the actual.

iii) Change in price: Another difficulty in calculating national income is that of price changes which fail to keep stable the measuring rod of money for national income. When the price level in the country rises, the national income also shows an increase even though the production might have fallen and vice versa. Thus due to price-changes the national income cannot be adequately measured.

iv) Illiteracy: In developing countries we find crores of people as illiterates. They do not keep proper accounts about the production and sales of their products. Under such circumstances, the estimates of production and earned incomes are simply a guess work.

v) Non-availability of Data: Adequate and correct production and cost data are not available. The data relating to crops, forestry, fisheries, animal husbandry and the activities of petty shop keepers, small enterprises, etc., are not counted. For estimating national income by the income method, data on unearned inijomes and on persons employed in the service sector are not available.

vi) Goods kept for self consumption: In India and other developing countries, producers keep a large portion of products for self consumption. For example, farmers keep certain portion of foodgrains for themselves. Such goods do not enter the market. It is not included in national income estimates.

vii) Absence of occupational specialization: The absence of occupational specialization makes calculation of national income difficult. Many people work as part-time workers and as such they do not give complete information about all sources of their income.

viii) Transfer Payments: The payments made by the Government to senior citizens, widows, scholarships, etc, are neglected while calculating the national income. But these are a part of individual income and a part of Government expenditure.

ix) Income from foreign companies: According to IMF, the income of foreign company should be included in the income of the host country and the profits earned by foreign companies should be included in the parent country. But it may not give correct national income estimates.

x) Existence of non-market transactions: Many times people stitch their own clothes, grow vegetables in their own garden and prepare many items in their own houses. The value of all such productive activities does not enter the market transactions and hence are not included in the national income estimates.

xi) Absence of trained personnel: There is a lack of well trained, skilled and efficient persons and staff to collect, classify and analyse the various information in relation to national income accounting.

Question 2.
Discuss the Macro-economic identities of national income Explain the important concepts of National Income.
Answer:
The Macro economic identities of national income are as follows:
a) Gross Domestic Product(GDP): GDP is the aggregate of the final goods and services produced in the domestic territory of a country during an accounting year. It is the total money value of all final goods and services produced within the country by the nationals of the country and by the foreign nationals staying in the country during a year. It does not include goods and services produced by non-resident Indians, It can be expressed as follows:
GDP = C + I + G + net ‘X’

where, C – Consumption expenditure of public,
I – Investment expenditure of private sector
G – Governments consumption and investment expenditure.
net X – Difference between value of exports and imports.

b) Net Domestic Product (NDP): NDP refers to the market value of all final goods and services turned out in an economy during a given period of time after making allowance for depreciation charges. It is obtained by subtracting depreciation from GDP.
NDP = GDP – Depreciation.

In simple words we can say that NDP is the net market value of final goods and services produced by its residents and non-residents with in the domestic territory of a country in a year.

c) Gross National Product (GNP):
It is the most important concept in N.I accounting. It-is a National concept. GNP is defined as the total market value of all final goods and services produced in a country in a year time.

No allowance for wear and tear cost i.e., depreciation is made. While calculating the GNP, the money value of only the goods and services which are finally consumed by the people are to be taken into account. Hence, the value of all intermediary goods and inputs are to be excluded in order to avoid double or multiple counting.

The income received from foreign investments and from other factor services rendered abroad should be added to the gross domestic product of a country. Similarly, the income generated by the foreigner in a given country should be deducted from the GDP for the purpose of computing the GNP.
GNP = GDP + X – M .
X= income earned by national abroad .
M= Income earned by foreigners in the given country.

GNP includes:

• The value of all consumption goods which are currently produced.
• The value of all capital goods currently produced.
• Total Government expenditure on buying various goods and services.
• Net export value
• Net amount earned abroad.
  GNP = (C+I+G) + ( X – M ) + (R – P)

d) Net National Product (NNP):
Net national product is the market value of the net output of final goods and services produced by the country during the relevant income period.
NNP = GNP- Depreciation.

e) Personal Income (PI):
The concept of personal income refers to the sum of all the incomes actually received by the individual and households in a country during one year. It is the amount available to them for spending, paying taxes and saving purposes PI is less than NI because several deduction are made out of it.

Personal income = National income – undistributed profit – social security contribution + transfer payment
The concept of PI helps us to know the potential purchasing power of people.

f) Disposable personal Income:
The entire PI accounting to individual or house hold in not available for consumption purpose.
A part of PI have to be paid to the Government by way of personal direct tax. Hence, that part of the personal direct taxes is called as disposable personal income.
DI = PI – Personal Direct Tax.

Disposable income can either be spent entirely of a part of the income can be saved. Therefore, the Personal Disposable Income may be written as:
PDI = Consumption Expenditure + Savings.

g) Nominal and Real National Income:
When the national income is expressed in the prices prevailing in the year in which it is calculated it is called nominal national income. For example, if the national income of the year 2014 – 15 is calculated as per the prices of 2014 – 15, it becomes nominal national income.

The real national income is expressed in terms of base year prices. While calculating National income, a particular year is taken as base year. The price level is assumed to be as 100 for the base year. The formula to calculate real national income is as follows:

h) Per Capita Income:
Per capita income refers to the income of an individual person. It is the average income of the people of a country. The per capita income is calculated by dividing the national income by population. Thus,

Question 3.
Explain the methods of measuring National Income.
Answer;
There are three methods of measuring national income, they are as follows:

a) Product methods or output method:
Under this method, a census of all goods and services are conducted to get the correct picture of total national production.
While,calculating total volume of goods and service, the following four items are to be included.

1. All kinds of consumption goods and services.
2. Gross domestic investment, which includes inventories, capital formation, construction of houses etc.
3. Production in the public sector.
4. Export minus imports.

b) Income method:
National income is the result of the combined and co-operative efforts put in by all factors of production. Alter employing them, we have to remunerate them in the form of rent, wages, interest and profits.

This method may be represented in the following equation.
Y = (r + w + i + p) + (X – M) + (R – P), where r – rent, w – wages, i – interest, p – profit, X – exports, M imports,  R – receipts, P – payments.

c) Expenditure method:
Incomes earned by factor inputs are spent on buying different goods and services. If we add the total expenditure incurred by all people in a years’ time, then we get total income of the people. Income determines the expenditures. All kinds of expenditures are to be taken into account while calculating the national income of a country. They are

i. Personal consumption expenditures of all people on all kinds of goods and services.
ii. Gross domestic investment or investment expenditures made by all businessmen in a year.
iii. Gross Governments’expenditure on all kinds of goods and services.
iv. Net foreign investment, exports – imports.

This method may be represented with the help of the following equation.
Y = (C +I + G) + (X – M) + (R – P), where, C – Consumption, I – Investment, G – Government’s Investment, X – exports, M – Imports, R – Receipts and P – Payments.