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A particle of mass m is moving in a circular path of constant radius r such that its centripetal acceleration (a) is varying with time t as a = k 2 rt 2 ,where k is a constant. The power delivered to the particle by the force acting on it is given as

1. Zero
2. mk 2 r 2 t 2
3. mk 2 r 2 t
4. mk 2 rt

Correct answer: mk 2 r 2 t

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