In the frictionless horizontal plane, the first blocks with masses of m, 2m and 3m, respectively, have a velocity v and the other blocks connected to the spring are in rest. Spring force is not impulsive. Since the spring coefficient is k and the collision coefficient is e, a) How long will the spring be (or shorten)? b) What is the smallest value of the kinetic energy of the system? Hint: The equations can be set up with respect to the moving axis whose origin is at the center of mass of the blocks connected to the spring. m v 2m k 3m