JEE Main202228 Jun 2022Morning ShiftPhysicsWork, Power and EnergyActual
A particle of mass m is moving in a circular path of constant radius r such that its centripetal acceleration a c is varying with time t as a c = k 2 r t 2 , where k is a constant. The power delivered to the particle by the force acting on it is -
Options
- AZero
- B2 m k 2 r 2 t
- Cm k 2 r 2 t
- D2 m k 2 r t
Correct answer
C. m k 2 r 2 t
Step-by-step solution
a c = k 2 r t 2 Or v 2 r = k 2 r t 2 Or v = k r t Therefore, tangential acceleration, a t = d v d t = k r Therefore, tangential force, F t = m a t = m k r Only tangential force does work. Power = F t v = m k r k r t ⇒Power = m k 2 r 2 t