Question

A particle of mass m is moving in a horizontal circle of radius r, under a centripetal force equal to `(-K//r^(2))`, where k is a constant. The total energy of the particle is -
A. `-K//r`
B. `-K//2r`
C. `K//2r`
D. `-2K//r`

Answer 1

Correct Answer - B
`F=(-K)/(r^(2))`
`KE=(1)/(2)Fr=(1)/(2)(-K)/(r^(2))xxr=-(k)/(2r)`