A 500 g block P rests on a frictionless horizontal table at a distance of 400 mm from a fixed pin O . The block is attached to pin O by an elastic cord of constant k = 100N/m and of undeformed length 900 mm . If the block is set in motion perpendicularly as shown in figure. The speed in the begining is such that the distance from O to the block P will reach the maximum value of 1.2 m. (assume there is no loss in energy due to jerk)
(A) Speed of projection is 4.5 m/*
(B) Speed of block when OP = 1.2 m is 2m/*.
(C) The radius of curvature of the path of the block when OP = 1.2 m is 3.75 cm
(D) The radius of curvature of the path of the block when OP = 1.2 m is 1.2 m