A hockey puck with a mass of 0.16 kg travels at a velocity of 40 m/s toward a goalkeeper. The goalkeeper has a mass of 120 kg and is at rest. Assuming a closed system, find the total momentum of the goalkeeper and puck after the puck is caught by the goalkeeper.

Question

In 3-4 sentences, identify the object with the greater momentum after the puck is caught and explain your reasoning.

Answer 1

The total momentum of a closed system is conserved, meaning it does not change. Before the puck is caught, the puck has a momentum of 0.16 kg * 40 m/s = 6.4 kg m/s towards the goalkeeper. After the puck is caught, the total momentum of the system will still be 6.4 kg m/s, but now all of that momentum will be carried by the goalkeeper since the puck has come to rest. Therefore, the goalkeeper will have the greater momentum after the puck is caught.