On a horizontal frictionless air table, a puck runs into an ideal horizontal spring that is fastened to the table. The puck compresses the spring by 15 cm before coming to rest. During the compression
Process, which quantities are conserved?
A) only the momentum of the puck
B) the momentum and the mechanical energy of the puck
C) only the kinetic energy of the puck
D) the momentum and the kinetic energy of the puck
E) only the mechanical energy (kinetic plus potential) of the puck

Question

Quizplus · Accepted Answer

During the compression of the spring by the puck on a frictionless surface, mechanical energy (kinetic plus potential energy) is conserved. The kinetic energy of the puck is converted into potential energy stored in the spring. Momentum is not conserved in this scenario because the spring exerts a force on the puck, changing its momentum.

On a Horizontal Frictionless Air Table, a Puck Runs into an Ideal