Physics MCQs Part 8

physics mcqs for all test preparation
71. The direction of the velocity of a body cannot change, when its acceleration is constant. The statement is.?
A. True
B. False
C. Uncertain
D. None of the above

72. What acceleration will a force of 5N impart to a mass of 5 kg.?
A. 5 N/kg
B. 5M/sec2
C. 1M/sec2
            D. None Of the above

73. When a body is accelerated.?
A. Its velocity always changes
B. Its direction always changes
C. Its speed always changes
D. Its falls towards the earth

74. A force of 100 dynes acts for 10 seconds on a body of mass500g. What is the change in momentum.?
A. 100 C.G.S. units
B. 10 C.G.S. units
C. 1000 C.G.S. units
D. 5000 C.G.S. units


75. We can clean a dirty carpet by beating. This is in accordance with.?
A. Newton's first law
B. Newton's second law
C. Newton's third law
D. None of the above

76. A force of 100 dynes acts on a body of 5 gms for 10 secs. What is the velocity produced.?
A. 2 fr/sec
B. 20 fr/sec
C. 200 fr/sec
D. 2000 fr/sec

77. Swimming is possible because of which law of motion.?
A. Second
B. First
C. Third
D. None of the above

78. A force of 150 dynes acts on a mass of 50 gms for 5 seconds. What is the accelerationproduced.?
A. 4 cms/sec2
B. 9 cms/sec2
C. 10c cms/sec2
D. None of these

79. A player caught a cricket ball of mass 150 gm. Moving at a rate of 20m/s. If the catching process be completed in 0.1 s. The force of the blow exerted by the ball on the hands is.?
A. 3000N
B. 300N
C. 30N
D. 30,000N

 80. The action and reaction forces referred in Newton's third law of motion.?
A. Must act upon the same body
B. Must act upon different bodies
C. Need not to be equal in magnitude but must have the same line of action
D. Must be equal in magnitude but need not have the same line of action