# 1. What happens to the gravitational force between two objects if the distance between them triples?

A. The force increases by a factor of 3

B. The force decreases by a factor of 9

C. The force increases by a factor of 9

D. The force decreases by a factor of 3

2. By what factor does the gravitational force between two objects increase if one object doubles in mass and the distance between them decreases by half?

A. 4

B. 2

C. 8

D. 1

3. What must be the units for the gravitational constant G in order for gravitational force to have units of newtons?

A. m3/(kg2⋅s2)

B. m3/(kg⋅s)

C. m3/(kg⋅s2)

D. m3/(kg2⋅s)

4. What happens to the gravitation force between two objects that are 15 m apart, when one of them moves 3 m closer?

A. It increases by a factor of 1 1/4

B. It decreases by a factor of 1 1/4

C. It increases by a factor of 1 9/16

D. It decreases by a factor of 1 9/16

5. In thinking about the uniform distribution of a gravitational field over a sphere, why does gravitational force have an inverse-square relationship with the distance between objects?

A. because the volume of a sphere is proportional to its radius

B. because the volume of a sphere is proportional to the square of its radius

C. because the surface area of a sphere is proportional to the square of its radius

D. because the surface area of a sphere is proportional to its radius

My answers:

1. B

2. C

3. A

4. B

5. D