1. Sir Isaac Newton (December 25th, 1642-1727)
1665
23 years old
Newton’s
Mountain

2. Newton’s Second Law

3. Newton’s Inverse Square Law of Gravitation

4. Henry Cavendish (1731 – 1810)
Vertical section drawing of Cavendish's torsion balance instrument including the building in which it was housed. The large balls were hung from a frame so they could be rotated into position next to the small balls by a pulley from outside. Figure 1 of Cavendish's paper

5. Henry Cavendish (1731 – 1810)

6. Law of Universal Gravitation
Where r = distance from center to center

7. Newton’s Shell Theorem – A uniform spherical shell of matter attracts a particle that is outside the shell as if all the shell’s mass were concentrated at its center.

8. Consider an apple at a distance rE from the center of the Earth.

9. A 50. kg student is 1. 0 m away from a 75 kg student
A 50. kg student is 1.0 m away from a 75 kg student. Calculate the force of gravitational attraction between them.

10. Consider an apple at a distance r from the center of the Earth.
Acceleration due to gravity at a distance r from the center of a planet
Where M = mass of the planet

11. Consider an apple at a distance rE from the center of the Earth.