One end of mass less inextensible string of length l is fixed and other end is tied to a small ball of mass m. The ball is performing a circular motion in vertical plane. At the lowest position, speed of ball is √(20gl) Neglect any other forces on the ball except tension and gravitational force. Acceleration due to gravity is g.
Let a be the magnitude of maximum possible rate of change of speed, and v be the speed when rate of change of speed is maximum. Then :
(A) a = 10ms–2
(B) a = 5ms–2
(C) v = √(9gl)
(D) v= √(18gl)
