Two identical rings, each of mass M and radius R, are standing on a rough horizontal surface. The rings overlap such that the horizontal line passing through their centre makes an angle of `theta = 45^(@)` with the radius through their intersection point P. A small object of mass m is placed symmetrically on the rings at point P and released. Calculate the acceleration of the centre of the ring immediately after the release. There is no friction between the small object and the rings. The friction between the small object and the rings, and the friction between the rings and the ground is large enough to prevent slipping.

Answer

`(mg)/(4M + m)`