Question

Craig is trying to push a heavy crate up a wooden ramp, but the crate won't budge. What is the direction of the static friction force acting on the crate?

1) Up the ramp
2) Down the ramp
3) Parallel to the ramp
4) Perpendicular to the ramp

Answer 1

The static friction force acting on the crate is up the ramp.

Step-by-step explanation:

The direction of the static friction force acting on the crate is up the ramp. When the crate is not moving, the static friction force opposes the force applied by Craig trying to push the crate up the ramp. This force acts parallel to the ramp, in the opposite direction of the push.