A particle of mass m is moving in a circul

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A particle of mass $m$ is moving in a circular path of constant radius $r$ such that its centripetal acceleration ${a_c}$ is varying with time t as, ${a_c} = {k^2}r{t^2}$, The power delivered to the particle by the forces acting on it is

A

$2\pi m{k^2}{r^2}t$

B

$m{k^2}{r^2}t$

C

$\frac{{m{k^4}{r^2}{t^5}}}{3}$

D

Zero

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, ${a_c} = {k^2}r{t^2}$, The power delivered to the particle by the forces acting on it is

Here the tangential acceleration also exits which requires power.

Given that ${a_C} = {k^2}r{t^2}$ and ${a_C} = \frac{{{v^2}}}{r}$

$\frac{{{v^2}}}{r} = {k^2}r{t^2}$

or ${v^2} = {k^2}{r^2}{t^2}$ or $v = krt$

Tangential acceleration $a = \frac{{dv}}{{dt}} = kr$

Now force $F = m \times a = mkr$

So power $P = F \times v = mkr \times krt = m{k^2}{r^2}t$