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Explanation for
Kepler’s Laws
•Momentum keeps the planets moving – you do not need some force to do this.
•Gravity provides the force which makes orbits
curve
–Gravity of Sun curves orbits of Planets
–Gravity of Earth curves orbit of moon (and also makes
objects on earth
fall downward)
•“Conservation of Angular Momentum” explains why motion is faster when closer to the sun.
•The inverse square law of gravity explains P2 µ a3 and the details of why the orbits are ellipses.
