Question

1. What do you need to change the momentum of a system?

2. What are the features of a typical modern running shoe? How does this change the ground reaction force during a heel strike when running with shoes compared to a heel strike when running without shoes?

3. When running with shoes how does the ground reaction force change from a heel strike run to a forefoot strike run?

Answer 1

1. Momentum (P) is a equal to mass (M) times velocity (V). But there are other ways to think about momentum! Force (F) is equal to the change in momentum (triangleP) over the change in Time (triangleT). And the change in momentum (triangleP) is also equal to the impulse (J)