A block of mass m1 = 1.8 kg slides along a frictionless table with a speed of 10 m/s. Directly in front of it, and moving in the same direction, is a block of mass m2 = 4.4 kg moving at 2.8 m/s. A massless spring with spring constant k = 1160 N/m is attached to the near side of m2, as shown in Fig. 10-35. When the blocks collide, what is the maximum compression of the spring? (Hint: At the moment of maximum compression of the spring, the two blocks move as one. Find the velocity by noting that the collision is completely inelastic to this point.) velocity of center of mass = (m1v1 + m2v2)/ (m1 + m2), energy = 1/2mv^2 = 1/2kx^2 my velocity of center of mass = (1.8x10 + 4.4x2.8)/(1.8 + 4.4) = 4.89m/s, i plugged that into the energy equations [KE = 1/2(m1 + m2)(4.89)^2 = 1/2kx^2], and tried to solve for x. I also solved for x without finding the velocity of the center of mass using relative velocity; the faster object is traveling @ 7.2 m/s relative to the other object, so i plugged that into the energy equations. they were all wrong, and i'm not sure how to solve this.