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

Newton’s Second Law

Newton’s Inverse Square Law of Gravitation

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

Henry Cavendish (1731 – 1810)

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

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.

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

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.

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

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