1. Acceleration Due to Gravity Gravity accelerates all objects in the same manner Any differences in freefall are due to air resistance Hammer and feather fall at the same rate on Moon… no atmospshere

2. Acceleration

3. Sir Isaac Newton

4. Newton’s Law of Gravitation

5. Newton’s Insight

6. Planetary Motion from Gravity

7. Kepler’s Laws Explained All three of Kepler’s law can be explained by Newton’s gravity Ellipses are special cases: bound orbits 2 nd law follows from central force and conservation of angular momentum Newton’s form of Kepler’s 3 rd law: p 2 = 4  2 a 3 G(M 1 +M 2 )