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mojo312
Nov 21, 2010, 04:39 PM
Two spheres are placed so that their centers are 2.9 m apart. The force between the two spheres is 2.85 10-12 N. What is the mass of each sphere if one sphere is twice the mass of the other sphere?
Kg (lighter sphere)
Kg (heavier sphere)

Unknown008
Nov 22, 2010, 08:34 AM
I assume that you are referring to the gravitational force between the two spheres.

Let the mass of the lighter sphere be m.

The mass of the other sphere will be 2m.

The force on one sphere due to the other is given by the formula:

F = \frac{GMm}{r^2}

M = 2m
m = m
F = 2.85x10^-12
r = 2.9
G = 6.67x10^-11

Find the value of m, hence the value of 2m.