Physics Chapter 2 Entry test MCQs
51. An engine pumps out 40 kg of water in one second. The water comes out vertically upwards with a velocity of 3ms-1 What is the power of engine in kilowatt?
a. 12 kW
b. 1.2 kW
c. 1200 Kw
d. 120 kW
52. An elevator’s motor produces 3000 W power. The speed with which it can lift a 1000 kg load is:
a. 3.06 ms-1
b. 30.6ms-1
c. 300.6ms-1
d. 0.306ms-1
53. The power needed to lift a mass of 5000g to height of 1 m in 2 second is
a. 245-watt
b. 2.45-watt
c. 2.45 k watt
d. 24.5 watt
54. An engine pulls a car of mass 1500 kg on a level road at a constant speed of 5ms-1 If the frictional force is 500 N, what power does the engine generate?
a. 2.5 kW
b. 5.0 kW
c. 12.5 kW
d. 10 kW
55. Work done on a body equals change in its———energy.
a. Potential
b. Total
c. Kinetic
d. All of these
56. If a certain force acts on an object and changes its kinetic energy from 65 J to 130 J then work done by the force will be:
a. 97.5 J
b. 92.5 J
c. 130 J
d. 65J
57. The amount of work required to stop a moving object is equal to:
a. The mass of the object times its velocity
b. The velocity of the object
c. The mass of the object times its acceleration
d. The kinetic energy of the object
58. The work energy principle is valid for
a. Change in P.E
b. Change in K.E
c. All type of energies
d. Change in E.Ρ.Ε
59. Mathematical form of work energy principle is
a. Fd = 1/2 mVf2 – 1/2 mVi2
b. Fd = 1/2 mVi2 – 1/2 mVf2
c. Fd = 1/2 mVf2 + 1/2 mVi2
d. Fd = 1/2 mVf – 1/2 mVi
PAST PAPER MCQS
60. A force 2i + j has moved its point of application from (2,3) to (6,5). What is work done?
a. +10
b. -10
c. +18
d. -18
61. 100 joules work has been done by an agency in 10 seconds. What is power of agency?
a. 100
b. 1000-watt
c. 0.10 watt
d. 10 watt
62. Work done on a body equals change in its energy.
a. Potential
b. Total
c. Kinetic
d. All of these
63. If a certain force acts on an object and changes its kinetic energy from 65 J to 130 J. then work done by the force will be:
a. 97.5 J
b. 92.5 J
c. 130 J
d. 65J
64. The consumption of energy by 60-watt bulb in 2 seconds is:
a. 120 J
b. 20J
c. 0.02 J
d. 30J
65. Which one of the following is a non-conservative force?
a. Elastic spring force
b. Electric force
c. Frictional force
d. Gravitational force
66. If velocity is double, then.
a. Momentum and K.E remain same
b. Momentum increase 4 times and K.E increases 2 times
c. Momentum increases 2 times and K.E increases 4 times
d. Momentum increases 2 times and K.E increase constant
67. The heat energy dissipated by 40 watts also in one hour is
a. 144000 J
b. 1440 J
c. 1440.000 J
d. 14400 J
68. The gravitational potential energy per unit mass is called:
a. P.E
b. Gravitational potential
c. Potential hill
d. Absolute P.E
69. A 6.0 kg block is released from rest 80m above the ground. When it has fallen 60m its kinetic energy is approximately:
a. 1200 J
b. 4800 J
c. 120 J
d. 3500 J
70. Potential energy per unit volume is given by
a. mgh/P
b. mgh
c. pgh
d. gh
71. Total word done in figure:
a. 24Nm
b. 8Nm
c. 16Nm
d. Zero Nm
72. Work done will be zero if angle between Force and displacement is:
a. 60°
b. 0°
c. 360°
d. 270
73. If mass ‘m’ is dropped from height ‘h’ vertically, f is the force of friction during downward motion and ‘v’ is the velocity at bottom, following equation will be hold:
a. mgh=1/2mv²-fh
b. 1/2mv²=mgh + fh
c. mgh=1/2mv² + fh
d. fh = mgh+1/2mv²
74. At what angle work done will be maximum?
a. 90°
b. 0°
c. 30°
d. 45°
75. Which one of the following is a greater work?
a. -100 J
b. +100 J
c. +200 J
d. -1000 J