A person carries a 25.0-N rock through the path shown in the figure,starting at point A and ending at point B.The total time from A to B is 1.50 min.How much work did gravity do on the rock between A and B?
A)625 J
B)20.0 J
C)275 J
D)75 J
E)0 J

Question

A person carries a 25.0-N rock through the path shown in the figure,starting at point A and ending at point B.The total time from A to B is 1.50 min.How much work did gravity do on the rock between A and B? 
A)625 J 
B)20.0 J 
C)275 J 
D)75 J 
E)0 J

Quizplus · Accepted Answer

Gravity does not do any work on the rock as it is carried horizontally from point A to point B. Work is only done if there is a force applied in the direction of the displacement. In this case, the force of gravity acting on the rock is perpendicular to the displacement from A to B, so no work is done.

A Person Carries a 25