Which of the following forces does NOT have a zero work done on the object:

Question

a)The normal force on a box that slides across a horizontal level floor.

b)The weight on a box that slides across a horizontal level floor.

c)The normal force on a box that slides down an inclined plane.

d)The weight on a box that slides down an inclined plane.

e)Actually all of the above describe forces that do zero work.

I think the answer is e) since all of them involve a force moving through a distance?

Answer 1

d)
In a, b, and c, the motion is perpendicular to the force and the force does no work.