1. 17-1 Physics I Class 17 Newton’s Theory of Gravitation

2. 17-2 Forces Known to Physics

3. 17-3 Newton’s Theory of Gravitation

4. 17-4 Newton’s Law of Universal Gravitation

5. 17-5 Properties of Gravity

6. 17-6 If Gravity Varies As 1/r 2, Where Does g = 9.8 m/s 2 Fit In?

7. 17-7 Gravity is a Conservative Force

8. 17-8 Class #17 Problems of the Day

9. 17-9 Kepler’s Three Laws of Planetary Motion 1. The Law of Orbits: All planets move in elliptical orbits having the Sun at one focus. 2. The Law of Areas: A line joining any planet to the Sun sweeps out equal areas in equal times. 3. The Law of Periods: The square of the period of any planet about the Sun is proportional to the cube of the semi-major axis of its orbit.

10. 17-10 Kepler’s Three Laws of Planetary Motion

11. The Law of Areas

12. The Law of Periods

13. ENERGY IN CIRCULAR ORBITS