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Roll No:
Application No:
Name:
Exam Date: 06-Oct-2020
Exam Time: 15:00-18:00
Examination: 1. Course Code - M.A./M.Sc./M.C.A.
2. Field of Study - PHYSICS (SPSM)
SECTION 1 - SECTION 1

Question No.1 (Question Id - 2)
What is the decimal value of binary 1011.11 ?
(A)
14.50
(B)
(C)
16.25
(D)
9.25
Question No.2 (Question Id - 14)
An ideal gas is kept at constant pressure `P'. The root mean square speed Vrms of the gas is doubled
by heating at constant volume. Calculate the pressure of the ideal gas after heating.
(A)
2P
(B)
(C)
6P
(D)
8P
Question No.3 (Question Id - 42)
The convex surface of a plano-convex glass lens with curvature radius 40 cm comes into contact with a
glass plate. A certain ring observed in reflected light has a radius 2.5 mm. Watching the given ring, the
lense was gradually removed from the plate by distance of 5 m. What has the radius of that ring
become equal to ?
(A)
6.00 mm
(B)
4.50 mm
(C)
3.00 mm
(D)
1.50 mm (Correct Answer)
Question No.4 (Question Id - 18)
How much heat must be absorbed by ice of mass m = 700 gm at -15C to take it to the liquid state at
10C ?
Given parameters.
Specific heat of ice(-15C) = 2220 J/kg.K
water = 4187 J/kg.K
Heat of fusion of water 333 kJ/kg.
(A)
233 kJ Approx
(B)
30 kJ Approx
(C)
286 kJ Approx (Correct Answer)
(D)
256 kJ Approx
Question No.5 (Question Id - 36)
The resistance of a semiconductor decreases on heating. This is because :
(A)
the material becomes harder on heating.
(B)
parallel channels of current flow become available.
(C)
more electrons become available for conduction. (Correct Answer)
(D)
the effective mass of an electron reduces on heating.
Case Study - 6 to 8 (Question Id - 45)

Question No.6 (Question Id - 46)
The value of closed loop voltage gain (AF) is :
(A)
(B)
30.11
(C)
60.33
(D)
90.66
Question No.7 (Question Id - 47)
What is the value of input resistance of the op-amp with feedback (RiF) ?
(A)
16.5 M
(B)
19.0 G (Correct Answer)
(C)
96 G
(D)
133 G
Question No.8 (Question Id - 48)
Total output offset voltage with feedback (VOOT) is :
(A)
? 7.15 mV
(B)
? 71.5 mV
(C)
? 1.36 mV (Correct Answer)
(D)
? 715 mV
Question No.9 (Question Id - 3)
(A)
4, 4, -4
(B)
3/2, 3/2, -3/2
(C)
2, 2, -2
(D)
1/2, 1/2, -1/2 (Correct Answer)
Question No.10 (Question Id - 19)
Let's take a carnot engine that operates between the boiling and freezing points of water. The engine
performs 1200 J of work per cycle in 0.5 sec. Find the energy delivered as heat to the low temperature
reservoir energy cycle.

(A)
1200 J approx.
(B)
3377 J approx.
(C)
4477 J approx.
(D)
3277 J approx. (Correct Answer)
Question No.11 (Question Id - 16)
A steel wire of original diameter 20.0 mm is subject to a tensile load up to fructure. Its diameter at
fructure is 16.0 mm. Find its ductility.
(A)
40%
(B)
(C)
32%
(D)
28%
Question No.12 (Question Id - 21)
(A)
3kr2
(B)
(C)
(D)
Question No.13 (Question Id - 13)
If W1 is the work done by an ideal gas at constant temperature `T' to expand from a volume V1 to a
volume 2V1. Let W2 be the work done by the same ideal gas at the same temperature to expand from
V2 to 4V2. Calculate the ratio W2/W1 ?
(A)
1
(B)
(C)
3
(D)
4
Question No.14 (Question Id - 20)
Let's assume that water is flowing with speed of 12 cm/sec through a horizontally placed tube of radius
2 cm. Find the speed of water flow under similar conditions, in case the radius of tube is doubled.
(A)
2 cm/sec
(B)
3 cm/sec (Correct Answer)
(C)
12 cm/sec
(D)
6 cm/sec
Question No.15 (Question Id - 25)
(A)
(B)
(C)

(D)
Question No.16 (Question Id - 43)
In Michelson's interferometer the light source composed of two wavelengths 600 nm and 600.6 nm. In
the process of translational displacement of one of the mirrors the interference pattern vanished
periodically. Find out the displacement of the mirror between two successive appearances of the
sharpest pattern.
(A)
30 mm
(B)
3 mm
(C)
0.3 mm (Correct Answer)
(D)
0.03 mm
Question No.17 (Question Id - 10)
Ultraviolet light of wavelength 350 nm and intensity 1.00 W/m2 is directed at a potassium surface. Find
the maximum kinetic energy of the photoelectrons. (h = 6.62 x 10-34 J.s and work function of potassium
= 2.5 eV)
(A)
0.3 eV
(B)
1.0 eV (Correct Answer)
(C)
3.3 eV
(D)
7.1 eV
Question No.18 (Question Id - 24)
Let's take a black total absorbing piece of cardboard of area A = 2.00 cm2, which intercepts light with
an intensity of 24 W/m2 from sunlight.
Find the radiation pressure produced on the cardboard by the light.
(A)
3 x 108 N/m2
(B)
8 x 10-8 N/m2 (Correct Answer)
(C)
3 x 10-8 N/m2
(D)
8 x 108 N/m2
Question No.19 (Question Id - 33)
An ideal gas undergoes an isothermal expansion (at temperature T) from volume V1 to V2. The entropy
change per mole is :
(A)
(B)
(C)
(D)
Question No.20 (Question Id - 35)
An electron gas is confined in a box of volume V. The number of electrons is N. The Fermi energy EF
at T = 0 K obeys :
(A)
(B)
(C)

(D)
Question No.21 (Question Id - 8)
Consider an ideal gas at pressure P1 and volume V1 undergoing free expansion to volume 2V1. Then
the gas is adiabatically expanded to a volume 16V1. Calculate the final pressure of the gas.
(A)
P1
(B)
(C)
(D)
Question No.22 (Question Id - 32)
A gas of particles obeys the Maxwell-Boltzmann distribution. The value of the average speed < v > is :
(A)
(B)
(C)
(D)
Case Study - 23 to 25 (Question Id - 49)
Question No.23 (Question Id - 50)
Find the total magnetic energy stored between the inner and outer conductor.
(A)
(B)
(C)
(D)
Question No.24 (Question Id - 51)
Find the electric field at any point r between the inner and outer conductor.

(A)
(B)
(C)
(D)
Question No.25 (Question Id - 52)
Calculate the energy transported by these magnetic and electric fields per unit time, per unit area at the
surface of inner conductor.
(A)
(B)
(C)
(D)
Question No.26 (Question Id - 31)
For a magnet, Ch and CM are the specific heats at constant magnetic field (h) and magnetization (M),
respectively. Which of the following statements is correct ?
(A)
Ch CM (Correct Answer)
(B)
Ch = CM
(C)
Ch CM
(D)
Ch may be greater or less than CM, depending on the material.
Question No.27 (Question Id - 9)
In a one-dimensional infinite square well of length `a', there are 6 x 109 electrons per meter. If all the
lowest energy levels are filled, determine the energy of the most energetic electron.
(h = 4.136 x 10-15 eV.s, C = 3x108m/s, me=9.1x10-31kg)
(A)
3.38 eV (Correct Answer)
(B)
13.25 eV
(C)
21.05 eV
(D)
27.28 eV
Question No.28 (Question Id - 22)
Suppose a long wire of radius `R' carries uniformly distributed current I. Find the magnetic field at point
`r' inside the wire.
(A)
(B)
(C)
(D)

Question No.29 (Question Id - 44)
A source of sonic oscillations with frequency 1700 Hz and a receiver is located on the same normal to a
wall. Both the source and receiver are stationary, and the wall recedes from the source with velocity
6.0 cm/s. Find out the beat frequency registered by the receiver. The velocity of sound is 340 m/s.
(A)
0.6 Hz (Correct Answer)
(B)
1.2 Hz
(C)
1.8 Hz
(D)
2.4 Hz
Question No.30 (Question Id - 38)
(A)
(B)
(C)
(D)
Question No.31 (Question Id - 4)
A 24 V, 600 mW zener diode is to be used for providing a 24 V stabilized supply to a variable load. If
input voltage is 32 V, calculate the series resistance R required and diode current when load resistance
is 12000 .
(A)
320 and 23 mA (Correct Answer)
(B)
650 and 15 mA
(C)
900 and 2 mA
(D)
1200 and 8 mA
Question No.32 (Question Id - 5)
What will be the cohesive energy of copper (FCC), given the bond energy between two copper atoms is
56.8 kJ/mol ?
(A)
92.6 kJ/mol
(B)
112.5 kJ/mol
(C)
340.8 kJ/mol (Correct Answer)
(D)
693.2 kJ/mol
Question No.33 (Question Id - 30)
A physical pendulum performs small oscillations about the horizontal axis with frequency 1 = 15.0 sec-
1. When a small mass m = 100 gram is fixed to the pendulum at a distance l = 20 cm below the axis,
the oscillation frequency becomes equal to 2 = 10.0 sec-1. Find out the moment of inertia (I) of the
pendulum relative to the oscillation axis.
(where acceleration of gravity g =10 m/sec2)
(A)
0.80 gram.m2
(B)
1.60 gram.m2 (Correct Answer)
(C)
2.40 gram.m2
(D)
3.20 gram.m2

Question No.34 (Question Id - 34)
Consider the phase diagram of water in the pressure-temperature plane. Which of the following
statements is false ?
(A)
It is possible to directly convert water vapour to ice.
(B)
It is possible to convert water vapour to water without a phase transition.
(C)
The triple point corresponds to the coexistence of three phases.
(D)
All phase transitions are characterized by a latent heat. (Correct Answer)
Question No.35 (Question Id - 23)
(A)
108
(B)
2
(C)
(D)
Question No.36 (Question Id - 17)
Calculate the maximum frequency of vibration in a one-dimensional lattice of identical atoms of mass
9.0 x 10-26 kg. If force constant of nearest neighbour interaction is 100 N/m.
(A)
10.61 x 1010 Hz
(B)
10.61 x 1012 Hz (Correct Answer)
(C)
10.61 x 1014 Hz
(D)
10.61 x 1016 Hz
Question No.37 (Question Id - 6)
(A)
(B)
(C)
(D)
Question No.38 (Question Id - 28)
Find the unit normal to the surface defined by xy3z2= 4 at (-1, -1, 2).
(A)
-4i - 12j + 4k
(B)
(C)
4i + 4j + 4k
(D)
-i + 3j + k
Question No.39 (Question Id - 11)
A material whose K absorption edge is 0.15 ? is irradiated with 0.08 ? X-rays. What is the maximum

kinetic energy of photoelectrons that are emitted from the K shell ?
(h = 4.136 x 10-15 eV.s)
(A)
11.3 keV
(B)
25.3 keV
(C)
72.3 keV (Correct Answer)
(D)
81.3 keV
Question No.40 (Question Id - 39)
(A)
(B)
e
(C)
e-/2
(D)
Question No.41 (Question Id - 7)
The resistivity of Si at 300 K is 3.16 x 103 ohm-m. The mobility of electrons and holes in Si are 0.14
m2/V-sec and 0.06 m2/V-sec respectively. The intrinsic carrier density is :
(A)
0.05 x 1019/m3
(B)
1.00 x 1016/m3 (Correct Answer)
(C)
4.01 x 1013/m3
(D)
6.02 x 1012/m3
Question No.42 (Question Id - 12)
In a Compton experiment an electron attains a kinetic energy of 0.200 MeV when an X-ray of energy
0.500 MeV strikes it. Determine the wavelength of the scattered photon if the electron is initially at rest.
(h = 4.136 x 10-15 eV.s)
(A)
9 x 10-12 ?
(B)
21 x 10-9 ?
(C)
43 x 10-6 ?
(D)
41 x 10-3 ? (Correct Answer)
Question No.43 (Question Id - 37)
In a photoelectric experiment, light of wavelength 700 nm is incident on a metal of work function 2 eV.
The maximum kinetic energy of emitted photoelectrons is :
(A)
1 eV
(B)
0.66 eV
(C)
0.33 eV
(D)
There is no photo-emission (Correct Answer)
Question No.44 (Question Id - 27)
(A)
2 k0r
(B)
4 k0r3
(C)
4 k0r (Correct Answer)
(D)

Question No.45 (Question Id - 15)
In a pure macroscopic, perfect crystal the major contribution to thermal resistance at normal
temperature is from :
(A)
Boundary scattering
(B)
Umklapp process (Correct Answer)
(C)
Impurity scattering
(D)
Harmonic vibration of lattice atom
Question No.46 (Question Id - 29)
(A)
(B)
3x-2
(C)
(D)
-7
Question No.47 (Question Id - 1)
Boolean function Y=(A+B)(A'(B'+C'))'+A'(B+C). What is the simplified form of Y ?
(A)
(B)
(A'+B'+C')
(C)
(AB+BC+AC)
(D)
ABC
Question No.48 (Question Id - 40)
The Laplace transform of cos2t is :
(A)
(B)
(C)
(D)
Question No.49 (Question Id - 41)

(A)
7
(B)
(C)
6
(D)
9
Question No.50 (Question Id - 26)
Find the electric field inside a solid sphere which carries a charge density proportional to the distance
from its origin, = kr where k is constant.
(A)
(B)