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प्रश्न
A stone of mass m is rotated in a circular path with a uniform speed by tying a strong string with the help of your hand. Answer the following questions
1) Is the stone moving with a uniform or variable speed?
2) Is the stone moving with a uniform acceleration? In which direction does the acceleration act?
3) What kind of force acts on the hand and state its direction?
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उत्तर
1) The stone is moving with uniform speed as given in the question.
2) Although the stone is rotating with uniform speed, its direction keeps on changing. Hence, the stone is said to be moving with uniform acceleration. The direction of acceleration is towards the center of the circle.
3) The force which acts on the hand is the centrifugal force. Its direction is opposite to the centripetal force, i.e. away from the center.
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