A small ball of mass m is suspended from the end A of a L shaped mass less rigid frame which is fixed to a block of mass m. The block is placed on a smooth table. The ball is given a horizontal impulse so as to impart it a velocity of `u`. The ball beings to rotate in a circle of radius R about the point A, while the block and the frame slide on the table. Find the tension in the string, to which the ball is attached, at the instant the ball is at the top most position. The rod does not interfere with the string during the motion.

Answer

`T=(m u^(2))/(R)-13 mg`