Question

1. when you jump off a small boat, the boat moves backward — why?

Explanation:

When you jump off the boat, you exert a force on the boat in the backward direction. According to Newton's third law of motion, for every action, there is an equal and opposite reaction. So the boat exerts an equal and opposite force on you in the forward direction (which helps you jump forward), and as a result, the boat moves backward.

Answer:

The boat moves backward due to Newton's third law of motion. When you jump forward (action), the boat experiences an equal and opposite reaction force pushing it backward.