A small sphere of mass m is tied to one end of a string of length l. The other end of the string is attached to a fixed point o . The sphere is released from position A when the string is horizontal and the sphere starts moving in a vertical circle. When the string makes an angle of θ with horizontal, centripetal acceleration of the sphere is,
If V be the speed of the sphere at position B,
Then conserving energy,
Centripetal acceleration at B,