Two blocks of masses m and M [M = 1.62m] are placed on a horizontal, frictionless surface. A light spring is attached to one of them, and the blocks are pushed together with the spring between them. A cord holding them together is burned, after which the block of mass M moves to the right with a speed of 1.62 m/s.
What is the speed of the block of mass m? Answer in units of m/s.