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Title: GR9277.004
Post by: conantee on January 09, 2010, 07:46:53 AM
Question 4-5
The magnitude of the Earth's gravitational force on a point mass is F(r), where r is the distance from the Earth's center to the point mass. Assume the Earth is a homogeneous sphere of radius R.

4. What is \frac{F(R)}{F(2R)}?
(A) 32
(B) 8
(C) 4
(D) 2
(E) 1