Summary
Circular Motion
- Centripetal (toward center) accel. a = v2/r
- Centripetal force f = ma
- Example: Ball on a string moving in a circle
Kepler’s Laws explained by gravitational force in Newton’s laws
Universal law of gravitation: f = G M m /r2
- The falling Apple and the Moon: each accelerates toward the earth obeying the same law!
- Motion on Earth and in the heavens obeying the same simple laws!
Force of gravity – extremely weak – large effects for large objects