A hockey puck sliding on a frictionless surface strikes a box at rest. After the collision, the two objects stick together and move at some final speed. Which of the statements describes the change in momentum and energy of the puck during the collision?

a. puck loses some but not all of its original momentum.
b. one cannot determine
c. puck conserves original momentum, but loses all mechanical energy
d. puck loses some momentum but conserves mechanical energy
e. puck loses conserves all momentum and mechanical energy
f. conserves momentum but loses some mechanical energy

Which of the following describes the change in momentum and energy of the combined puck and box?

a. system loses some but not all of its original momentum.
b. one cannot determine
c. system conserves original momentum, but loses all mechanical energy
d. system loses some momentum but conserves mechanical energy
e. system loses conserves all momentum and mechanical energy
f. conserves momentum but loses some mechanical energy