A body is tied at the end of a string and whirled round in a horizontal circle . At any instant, its kinetic energy is found to be numerically equal to the centripetal force acting on it . Then the radius of the circle will be

Options

A. `1//2 m `
B. 1 m
C. 2 m
D. 4 m

Answer

C

Explanation

`K.E=C.F.`
`(1)/(2)mv^(2)=(mv^(2))/(r) therefore r=2m`