Question

The centers of a 10 kg lead ball and a 100 g lead ball are separated by 9 cm.

(a) What gravitational force does each exert on the other?
___N

(b) What is the ratio of this gravitational force to the weight of the 100 g ball?
F / W_{100 g} = ____

Answer 1

a) for the gravitational force

gravitational force = G * mass1 * mass2/distance^2

gravitational force = 6.67 *10^-11 * 10 * 0.100/.09^2

gravitational force = 8.23 *10^-9 N

the gravitational force on the lead ball is 8.23 *10^-9 N

b)

weight of 100 gm ,W100 = 0.10 * 9.8

W100 = 0.98 N

ratio of this gravitational force to the weight of the 100 g ball = (8.23 *10^-9/.98)

ratio of this gravitational force to the weight of the 100 g ball = 8.39 *10^-9

the ratio of this gravitational force to the weight of the 100 g ball is 8.39 *10^-9