85. One half of a vibration of a body, is called
A. period time
B. oscillation
C. beat
D. amplitude.

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86. Periodic time of a particle moving with simple harmonic motion is the time taken by the particle for
A. half oscillation
B. quarter oscillation
C. complete oscillation
D. none of these.

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87. Periodic time of body moving with simple harmonic motion, is
A. directly proportional to its angular velocity
B. directly porportional to the square of its angular velocity
C. inversly proportional to the square of its angular velocity
D. inversely proportional to its angular velocity.

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88. For a body moving with simple harmonic motion, the number of cycles per second, is known as its
A. oscillation
B. amplitude
C. periodic time
D. frequency.

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89. The piston of a steam engine moves with a simple harmonic motion. The crank rotates 120 r.p.m. and the stroke length is 2 metres. The linear velocity of the piston when it is at a distance of 0.5 metre from the centre, is
A. 5.88 m/sec
B. 8.88 m/sec
C. 10.88 m/sec
D. 12.88 m/sec,

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90. A particle moving with a simple harmonic motion, attains its maximum velocity when it passes
A. the extreme point of the oscillation
B. through the mean position
C.( c) through a point at half amplitude
D. none of these.

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91. Pick up the incorrect statement from the following. In a simple harmonic motion
A. velocity is maximum at its mean position
B. velocity is minimum at the end of the storke
C. acceleration is minimum at the end of the stroke
D. acceleration is zero at the mean position.

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