# A body of mass 𝑚 𝑘𝑔 is rotating in a vertical circle at the end of a string of length 𝑟 metre. The difference in the kinetic energy at the top and bottom of the circle is

Question: A body of mass 𝑚 𝑘𝑔 is rotating in a vertical circle at the end of a string of length 𝑟 metre. The difference in the kinetic energy at the top and bottom of the circle is

(A) $\dfrac{mg}{r}$

(B) $\dfrac{2mg}{r}$

(C) 2𝑚𝑔r

(D) 𝑚𝑔r