15 joules of work are done by forces other than gravity in taking an object from a position 3 m above the ground to a position 8 m above the ground. What is the change in the gravitational potential energy of the object?

o A. It decreases by 5 joules.

o B. It increases by 5 joules.

o C. It increases by 11 joules.

o D. It increases by 15 joules.

1 answer

Correct Answer: D — It increases by 15 joules.
Explanation: The amount of work done by non-gravitational forces in moving an object from one position to another is equal to the change in the gravitational potential energy of the object. If 15 joules of work are done on the object by non-gravitational forces, then the gravitational potential energy of the object is increased by 15 joules.