A heavy suitcase is carried by a porter down a flight of stairs. The work done on the suitcase by the porter is
A) zero.
B) positive.
C) negative.
D) unknown; more information is needed to work out the answer.

Question

Quizplus · Accepted Answer

The work done by the porter on the suitcase is negative because the force exerted by the porter is in the opposite direction to the displacement of the suitcase as it is moved down the stairs.

A Heavy Suitcase Is Carried by a Porter Down a Flight