Lab+12+-+Collisions

__Lab 12 - Collisions__ m1 = 515g = 0.515kg v1 = 0.682m/s m2 = 515g = 0.515kg v2 = 0.585m/s m1v1 = m2v2 (0.515kg)(0.682m/s) = (0.515kg)(0.585m/s) 0.351kgm/s = 0.301kgm/s 85.76% conservation of momentum. Close enough.

Ki = 0.5mv^2 = 0.5(0.515)(0.682^2) = 0.11976943J Kf = 0.5mv^2 = 0.5(0.515)(0.585^2) = 0.0881229375J 73% conservation of kinetic energy. Little kinetic energy loss to the the lack of a completely frictionless surface and completely elastic collision. m1 = 1015g = 1.015kg v1 = 0.680m/s m2 = 551g = 0.551kg v2 = 0.593m/s m1v1 = m2v2 (1.015kg)(0.680m/s) = (0.551kg)(0.593m/s) 0.690kgm/s = 0.326kgm/s 47% conservation of momentum Not close enough. I am not entirely sure why this particular video and graph show a significant loss in momentum which is not possible. I would have to guess that the first mass did not collide with the second one completely elastically, thus not transferring all of its momentum. My recollection is that in some of the videos, the blue cup actually recoiled backwards or continued drifting forward for a small distance which would have indicated a lack of complete transfer of momentum. This is also supported by the extreme difference in the final and initial kinetic energy of the system.

Ki = 0.5mv^2 = 0.5(1.015)(0.680^2) = 0.234668J Kf = 0.5mv^2 = 0.5(0.515)(0.585^2) = 0.0968792995J 41% conservation of kinetic energy m1 = 515g = 0.515kg v1 = 0.569m/s m2 = 1030g = 1.03kg v2 = 0.235m/s (0.515kg)(0.569m/s) = (0.293kgm/s)/(0.515kg + 0.515kg) = 0.285m/s Real velocity = 0.235m/s 21.276% error Close enough.

Ki = 0.5mv^2 = 0.5(0.515)(0.569^2) = 0.083368J Kf = 0.5mv^2 = 0.5(1.03)(0.235^2) = 0.028441J 34% conservation of kinetic energy. Loss of kinetic energy.

m1 = 1015g = 1.015kg v1 = 0.564m/s m2 = 1530g = 1.530kg v2 = 0.334m/s (1.015kg)(0.564m/s) = (0.572kgm/s)/(1.530kg) = 0.374m/s Real velocity = 0.334m/s 11.976% error Close enough.

Ki = 0.5mv^2 = 0.5(1.015)(0.564^2) = 0.161434J Kf = 0.5mv^2 = 0.5(1.530)(0.334^2) = 0.08543J 52.91% conservation of kinetic energy. Loss of kinetic energy.