Enter the normal force and friction force into the coefficient of friction calculator below. Evaluate the coefficient of friction between two surfaces.

## Coefficient of Friction Formula

The following formula is used in the coefficient of friction calculator above:

u = F / N

- Where u is the coefficient of friction
- F is the force due to friction
- N is the normal force

This can be used in both static and kinetic friction cases. In a static friction case, the force applied, P, will never exceed the frictional force F. Otherwise the object would be in motion and this would be a kinetic friction case.

## Coefficient of Friction Definition

A coefficient of friction is defined as the unitless factor between two surfaces that resist movement when under a normal force.

## How to calculate a coefficient of friction?

How to calculate coefficient of friction

**First, determine the net horizontal force acting on an object.**Calculate the net force acting on a stationary or moving object.

**Next, determine the normal force acting on an object.**When analyzing a single object with no extra vertical forces, the normal force should be equal to the weight.

**Calculate the coefficient of friction**Calculate the coefficient of friction using the normal force and net horizontal force.

## FAQ

**What is a coefficient of friction?**

A coefficient of friction is a term in physics use to describe the resistant force acting on an object due to it’s normal force and the two surfaces that are in contact.

**What is the difference between static and dynamic friction?**

Static friction is the force between stationary objects and dynamic friction is the force between moving objects.