1. The problem statement, all variables and given/known data Two blocks of mass 3 kg and 6kg are placed on a smooth horizontal surface.They are connected by a light spring of force constant k=200N/m. Initially the spring is unstretched. The block of mass 3 kg is imparted a velocity of 1m/s and the block of mass 6 kg is imparted 2 m/s (in opposite directions). Find the maximum extension of the spring. The answer is 30 cm. 2. Relevant equations 3. The attempt at a solution I thought we can equate the sum of the Kinetic energies of the two blocks to 1/2kx2. But will there be 2 extensions x1 and x2 for both the blocks? In that case how will I find both? IS there a relation between them?