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Question
Is it possible that an object is in a state of accelerated motion due to external force acting on it, but no work is being done by the force? Explain it with an example.
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Solution
Yes, it is possible that an object is in a state of accelerated motion due to external force acting on it, but no work is being done by the force.
For example, an object moving in a circular path due to centripetal force acting on it.
At any instant of time, a constant acceleration due to the centripetal force act on the object along the radius towards the centre while the direction of displacement is tangential to the circle. That is, force and displacement are perpendicular to each other and hence no work is being done.
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