Question
A small ball of mass 1kg and charge 2 C 3 is placed at the centre of a uniformly charged sphere of radius 1m and charge 1mC 3 . A narrow smooth groove is made in the sphere from centre to surface as shown in figure. The sphere is made to rotate about its vertical diameter at a constant rate of 1 2 revolutions per second. Find the speed w.r.t. ground with which the ball slides out from the groove. Neglect any magnetic force acting on ball