Model Questions for Engineering Entrance Tests Part - 2
( Physics) 

51. A train, 300 m long is traveling with a velocity of 144 km/hr. It passes over a bridge in 120 seconds. Then the length of the bridge is
a. 4.5 km
b. 2.25 km
c. 4.5 m
d. 2.25 m
Ans: A

52. Water has maximum density at
a. 140C
b. 100C
c. 0.40C
d. 40C
Ans: D

53. The magnifying power of a Galilean telescope in normal setting is 15 and its length is 112 cm. The focal length of its eye piece lens
a. 16 cm
b. 119 cm
c. 8 cm
d. 105 cm
Ans: C

54. A bimetallic element is a device in which two thin flat strips of different metals are rivetted together. Such a device can only be used as:
a. Thermister
b. Thermionic
c. Thermocouple
d. Thermostat
Ans: D

55. For a given kinetic energy the smallest de Broglie wavelength is for
a. proton
b. neutron
c. α-particles
d. electron
Ans: C

56. Young's interference experiment is performed with red light of wavelength 7000Ã… and the fringes formed at a distance of one metre has width β. Now red light is replaced by a light of wavelength 4000Ã…. In order that the fringes should again have the same band width β, the screen should be kept at a distance of
a. 7/3m
b. 4/7m
c. 7/4m
d. 3/7m
Ans: C

57. Two polaroids are kept crossed to each other. Now one of them is rotated through a angle of 450. The percentage of incident light now transmitted through the system is
a. 15%
b. 75%
c. 25%
d. 50%
Ans: C

58. Two capacitors 10 μF and 25 μF are charged to a potential of 100 V each. They are connected in parallel. The potential across them are
a. 100 V each
b. 200 V each
c. 50 V each
d. 80 V and 120 V
Ans: A

59. The equation of a harmonic wave is given by y = 0.05 sin (2000t − 8x)m. The maximum particle velocity of the particle in the wave is (in proper units)
a. 100
b. 10
c. 2000
d. 100
Ans: A

60. For a heat engine the temperature of the source is 1270C. To have 60% efficiency the temperature of the sink is
a. 1130C
b. −1130C
c. −2730C
d. 1600C
Ans: B

61. The temperature of a gas is produced by:
a. The kinetic energy of the molecules
b. The repulsive forces between the molecules
c. The potential energy of the molecules
d. The attractive force between the molecules
Ans: A

62. Energy generation in star is mainly due to
a. Fission of heavy nuclei
b. Chemical reactions
c. Fusion of heavy nuclei
d. Fusion of light nuclei
Ans: D

63. Using a convex lens a clear image of a candle flame is produced on a screen. How many other clear images can be received on this screen if only the lens is to be shifted?
a. Two more
b. A large number
c. Only one more
d. None
Ans: C

64. When a torque acting upon the system is zero. Which of the following will be constant
a. Angular momentum
b. Force
c. Linear momentum
d. Linear impulse
Ans: A

65. A body is perfectly elastic if
a. It can be easily deformed
b. It can be easily compressed
c. It can readily drawn into a wire
d. It recovers its original shape or volume on the removal of the deforming forces
Ans: D

66. If the units of length and force be each increased four times, the units of energy is increased
a. 16 times
b. 8 times
c. 4 times
d. 32 times
Ans: A

67. Compressed air coming out of a punctured ball becomes cooler because of
a. isothermal expansion
b. isothermal compression
c. adiabatic expansion
d. adiabatic compression
Ans: C

68. Two conducting spheres of radii 2cm and 4cm are charged. They are now kept in constant and separated. The ratio of their potential is
a. zero
b. 2:1
c. 1:1
d. 1:2
Ans: C

69. In a series LCR circuit, at resonant frequency
a. the impedance is maximum
b. the current and voltage are in phase
c. current is minimum
d. the impedance and current are maximum
Ans: B

70. In the steady state of temperature for a body, the rate of flow of heat across it depends upon:
a. Only its thermal conductivity
b. Only its thermal capacity
c. Neither on its thermal capacity nor its thermal conductivity
d. Both its thermal capacity and its thermal conductivity
Ans: A

71. The process of fission, splitting of a heavy nucleus into smaller nuclei with emission of energy etc, occurs primarily in
a. The Sun
b. Chemical reactions
c. Nuclear reactor
d. The hydrogen bomb
Ans: C

72. A storage cell of emf 10 V and internal resistance 0.1Ω, is charged with 5 amps. Then the terminal voltage is
a. 10 V
b. 9.5 V
c. 10.5 V
d. 9.9 V
Ans: C

73. On which natural phenomenon is the unit of time based?
a. Diurnal motion of the earth
b. Rotation of the sun
c. The revolution of the moon
d. Rotation of the moon
Ans: A

74. What causes 'Reverberation'?
a. Reflection
b. Refraction
c. Interference
d. Diffraction
Ans: A

75. A body of mass m is resting on an inclined plane which makes an angle θ with the horizontal. As θ increases the normal reaction of the plane
a. Decreases
b. Increases
c. Remains unaltered
Ans: A

76. Two unlike parallel forces P and 2P act at points A and B. Their resultant acts at a point
a. A
b. between A and B
c. on AB produced
d. on BA produced
Ans: C

77. When two turning forks A and B are sounded together four beats per second are heard. If the frequency of A is 256 Hz, find that of B. On loading the fork B, the number of beats decreases.
a. 252 Hz
b. 264 Hz
c. 248 Hz
d. 260 Hz
Ans: D

78. Natural magnetism of a magnetic material is explained due to
a. spin of electron
b. association with earth magnetic field
c. nucleus
d. spin and rotation of electron
Ans: D

79. The presence of dissolved impurities in water:
a. Does not affect its boiling point
b. Lowers its boiling point
c. Raises its boiling point
d. Does not let water boil
Ans: C

80. A proton has a mass of 1.67×10-27 kg and charge of 1.6×10-19 C. If the proton be accelerated through a potential difference of one million volts, then the KE is
a. 1.6×10-13 J
b. 1.6×10-15 J
c. 1.67×10-13 J
d. 1.67×10-15 J
Ans: A

81. When a light is refracted, which of the following does not change?
a. Velocity
b. Amplitude
c. Frequency
d. Wavelength
Ans: C

82. 540 gm of ice at 00C is mixed with 540 gm of water at 800C. The final temperature of the mixture in 0C will be
a. 20
b. 0
c. 40
d. 80
Ans: B

83. The process in which nuclei join to form a new nucleus and liberate heat is known as
a. Fusion
b. Fission
c. Electrolysis
d. Catalysis
Ans: A

84. Speed of the gas ejected from a rocket is 1000ms-1 and the force experienced as a result is 50 N. The mass of gas escaping per second is
a. 5 g
b. 200 g
c. 50 g
d. cannot determined
Ans: C

85. A potentiometer consists of a wire of length 4m having a resistance 10Ω. It is connected to a cell of emf 2V. The potential difference per unit length of the wire will be
a. 2 V/m
b. 5 V/m
c. 0.5 V/m
d. 10 V/m
Ans: C

86. The magnetic potential at any point on the equatorial magnet is
a. Infinite
b. Zero
c. Positive
d. Finite
Ans: B

87. A ball hangs from a string inside a train moving along a horizontal track. The string is observed to incline towards the front of the train making a small angle with the vertical. It shows that the train is
a. Moving with uniform acceleration
b. Moving with constant retardation
c. Moving with uniform velocity
d. At rest
Ans: B

88. Speed of flow of viscous liquid through a capillary tube of radius r under constant pressure head is proportional to
a. r
b. r2
c. r4
d. r−1
Ans: B

89. At the temperature of inversion, the emf in a thermocouple is
a. minimum
b. maximum
c. half the maximum value
d. zero
Ans: D

90. A number of images of a candle flame can be seen in a thick mirror. The brightest image is:
a. The last one
b. The first one
c. The second one
d. The third one
Ans: C

91. Cathode rays are
a. A stream of positive charges
b. A stream of negative charges
c. A stream of neutral particles
d. Electromagnetic waves
Ans: B

92. The dimension of entropy is
a. M0L−1T0K
b. ML2T−2K−1
c. M0L−2T0K2
d. MLT−2K
Ans: B

93. A glass prism of refractive index 1.5 will simply act as a glass slab when kept in liquid of refractive index
a. 1
b. 1.5
c. 2
d. √2
Ans: B

94. Cyclotron is used for accelerating
a. Protons
b. Lead
c. Atoms
d. Molecules
Ans: A

95. Mirage is the phenomenon due to
a. Total internal reflection
b. Interference of light
c. Polarization of light
d. Diffraction of light
Ans: A

96. Short sight is due to
a. The eye-ball being too short for the eye lens
b. A defect in the retina
c. The eye-ball being too long for the eye lens
d. A defect in the cornea
Ans: C

97. Radius of first orbit of the electron in a hydrogen atom is 0.53Ã…. Radius of the third orbit is
a. 2.12Ã…
b. 0.18Ã…
c. 4.77Ã…
d. 1.06Ã…
Ans: C

98. In a working nuclear reactor, cadmium rods are used to
a. Absorb all neutrons
b. Absorb some neutrons
c. Speed up neutrons
d. Slow down neutrons
Ans: B

99. A bullet fired from a gun has a force on it given by F=400−8×104 t, such that force becomes zero as soon as the bullet leaves the barrel of the gun. The impulse imparted to the bullet
a. 0.1 NS
b. 2 NS
c. 1 NS
d. zero
Ans: C

100. In a P-type semiconductor the acceptor impurity level are a little
a. below the valance band
b. above the conductor band
c. above the valence band
d. below the conduction band
Ans: C