A classical mechanics problem by Pradumn Srivastava

Classical Mechanics Level 4

The kinetic energy $k$ of a particle moving along a circle of radius $R$ depends on distance covered s as $k=as^2$ where $a$ is a positive constant. The total force acting on particle is:

NONE OF THE ABOVE 2a[{R^2}/s] 2as[1+{s^2}/{R^2}]^{1/2} 2as[{s^}/R] 2as