1. Newton’s Law of Gravitation Chapter 7, Section 3 Pg. 263-265

2. Newton’s Universal Law of Gravitation Earth MOON FgFg To keep two moving bodies from shooting off in a straight line, a mutual gravitational force attraction occurs between them. FEmFEm FmEFmE

3. The amount of gravitational force that occurs between two masses depends on the distance between the two masses. Newton’s universal law of gravitation F g = (G m 1 m 2 ) /r² G = constant of universal gravitation G = 6.673 x 10 -11 Nm²/kg²

4. Sample Problem 2 Find the distance between a 0.300 kg billiard ball and a 0.400 kg billiard ball if the magnitude of the gravitational force is 8.92 x 10 -11 N. r = ? m 1 = 0.300 kgm 2 = 0.400 kg Fg = (G m 1 m 2 ) /r² F g = 8.92 x 10 -11 N r² = (G m 1 m 2 ) / Fg r = √(G m 1 m 2 ) / Fg r = √[6.673 x 10 -11 Nm²/kg² (0.4 kg) (0.3kg)]/8.92x10 -11 N r = 3.00 x 10 -1 m G = 6.673 x 10 -11 Nm²/kg²