ac=k2rt2
Or rv2=k2rt2 Or v=krt
Therefore, tangential acceleration, at=dtdv=kr
Therefore, tangential force, Ft=mat=mkr
Only tangential force does work.
Power=Ftv=(mkr)(krt) ⇒Power=mk2r2t
JEE Main 2022 — Physics Mechanics
A particle of mass m is moving in a circular path of constant radius r such that its centripetal acceleration ac is varying with time t as ac=k2rt2 , where k is a constant. The power delivered to the particle by the force acting on it is -
Held on 28 Jun 2022 · Verified 6 Jul 2026.
Zero
2mk2r2t
mk2r2t
2mk2rt
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