Plyure 2. After the collision Figure 2. After the Collision Block X of mass M travels in the positive direction with a speed vx toward block Y of mass M that is at rest, as shown in Figure 1. After the collision, block Y travels with a speed of vy in the positive direction while block X remains at rest. The horizontal surface that the blocks slide across is considered to be smooth. How can a student determine whether the collision is elastic or inelastic? A The student only needs to observe that the blocks do not stick together after the collision, which means that the collision is elastic. B The masses of both blocks are known, and the initial and final velocities are both blocks are known. Therefore, the student must compare the initial momentum of the two-block system before the collision and after the collision using Ipo = pz. С The masses of both blocks are known, and the initial and final velocities are both blocks are known. The student should use Ap = mAv for either block X or block Y to determine how much the block's momentum has changed. The masses of both blocks are known, and the initial and final velocities are both blocks are known. Therefore, the student must compare the initial kinetic energy of the two- block system before the collision and after the collision using AK = mAv?​