We are trying to move a crate across a rough surface. We keep increasing the force until the crate starts moving. Since there is a range of magnitudes of a force, this means that kinetic friction has a range of values before the crate starts moving.

Question

Quizplus · Accepted Answer

The range of magnitudes of force before the crate starts moving is related to static friction, not kinetic friction. Kinetic friction comes into play only after the object has started moving, and it typically has a single value for a given combination of surfaces and normal force.

We Are Trying to Move a Crate Across a Rough