A block of known mass M is at rest at the base of a ramp. A second identical block of mass M travels at a known, constant velocity vo, as shown in Figure 1. The block that travels at a constant speed collides with and sticks to the first block. Both blocks slide up the ramp and travel with an unknown velocity UR at the top of the ramp, as shown in Figure 2. All frictional forces are considered to be negligible. Which quantity should the student measure, if any, to determine whether the conservation of momentum applies to the two-block system from immediately before the collision to immediately after the blocks have reached the top of the ramp while stuck together? Justify your selection. B The force due to gravity exerted on both blocks as they travel up the ramp, because the force due to gravity does work on the system as it travels up the ramp. The time in which the blocks travel up the ramp, because this can be used to determine the change in momentum of the system from before the collision to after the collision. The acceleration of both blocks as they travel up the ramp, because this can be used to determine the average net force exerted on the blocks. The velocity up of the two-block system at the top of the ramp, because this can be used to determine the final momentum of the M Vo M Figure 1. Before the collision Figure 2. After the collision VR MM