# A particle of mass 'm' moves along a circle of radius R with a normal acceleration varying with time as a=b*t^2 where b is a constant.The time dependence of the power developed by all the forces acting on the particle is:a) 2mRbt b)mRbt c)4mRbt d)3mRat

Ramesh V
70 Points
13 years ago

normal accln: an = v2/R = bt2

so v2 = bt2R

Kinetic Energy(E) = 1/2 mv2 = 1/2*mbt2R

power P =dE/dt = d(1/2*mbt2R) / dt

P =mbt2R

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Naga Ramesh
IIT Kgp - 2005 batch

JAGABANDHU PANDA
8 Points
13 years ago

Hi

I would like to make some corrections to the reply posted by Mr Ramesh. I think after differentiation of "E" we would be getting P = mRbt which is the answer i. e. the answer is the option (b).

JAGABANDHU PANDA
8 Points
13 years ago

Hi

The differentiation needs to be corrected and accordingly the answer is (b)

JAGABANDHU PANDA

IIT Delhi