Q. 139. The arrangement shown in figure is in equilibrium with all strings vertical. The end A of the string is tied to a ring which can be slid slowly on the horizontal rod. Pulley P, is rigidly fixed but P can move freely. A mass m is attached to the centre of pulley P, through a thread. Pulleys and strings are mass less. A 7177 P. MI P. (a) Which block will move up as A is moved slowly to the right? (b) Will the block of mass m have horizontal displacement? (c) Is it possible, for a particular position of A, that M has no acceleration but m does have an acceleration? If this happens when string from P, to A makes an angle with vertical, find the acceleration of m at the instant