posted by Andrea .
A block of mass m1=1.6kg, initially moving to the right with a velocity of +4m/s on a frictionless horizontal track, colides with a massless spring attached to a second block of m2=2.1kg moving left with a velocity of -2.5m/s. The spring constant is 600 N/m.
A) assuming the collision is elastic determine the velocity of block 2 at the instant when block 1 is moving to the right with a velocity of +3m/s.
B) find the compression in the spring.