Two rectangular blocks A and B of masses 2kg and 3 kg respectively are connected by spring of spring constant 10.8 ${\rm{N}}{{\rm{m}}^{ - 1}}$ and are placed on a frictionless horizontal surface. The block A was given an initial velocity of 0.15 $m{s^{ - 1}}$ in the direction shown in the figure. The maximum compression of the spring during the motion is