An apple weighing 3 newtons hangs, motionless, from a tree branch. What are the forces by the environment that act on this apple?
A) Only the upward lift of the branch.
B) the apple's weight and the branch's upward lift on the apple.
C) Only the apple's weight.
D) There are no forces by the environment on a motionless apple.
E) The apple's weight and the apple's downward pull on the branch.

Question

Quizplus · Accepted Answer

The apple is motionless, so the net force on it must be zero. The only two forces acting on the apple are its weight (downward) and the upward lift of the branch. These two forces must be equal in magnitude and opposite in direction in order for the apple to be motionless.

An Apple Weighing 3 Newtons Hangs, Motionless, from a Tree