Newton ’ s Law of Universal Gravitation

1. Newton’s Law of Universal Gravitation Dan Li SUNY-Stony Brook 12/09/2002

2. Outline • Who Found It? • The Statement of the Law • Gravity Near the Earth’s Surface • Geophysical Applications • Satellites

3. Who Found It?

4. The Statement of the Law • Magnitude: Every particle in the universe attracts every other particle with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between them. • Direction: This force acts along the line joining the two particles.

5. Gravity Near the Earth’s Surface

6. Some Geophysics

7. Some Geophysics: Applications Variation in g: Gravity Anomalies To investigate • the structure of the Earth’s crust • mineral deposit • oil exploration Some examples • mineral deposit • oil exploration

8. Satellites • What keeps a satellite up? Its high speed • How they move?

9. Moon: Special Satellite

10. Earth: the Satellite of the sun

11. Summary • a force “acting at a distance” even though there is no contact • a useful tool to explore in space

12. Thank you!