# Get to Know How to Calculate the Coefficient of Kinetic Friction

What is the kinetic friction coefficient? How is it calculated? Read to find all the answers.

ScienceStruck Staff

Last Updated: Nov 21, 2018

What is Kinetic Friction?

Friction is the macroscopic force that opposes relative motion between any two surfaces, at the point of contact. The surfaces might be a solid and a fluid, two fluids, or a solid-fluid interface. When the two surfaces in contact are solids, it's called 'Dry Friction', for reasons that are self-explanatory.

The Coefficient

Dry friction has been theoretically modeled in physics so that it can be quantified. This coefficient is a concept that emerges in its empirical theory. The perpendicular force between two surfaces in contact with each other is called the normal force.

F

_{f}= μ

_{Kinetic}F

_{N}where μ

_{Kinetic}is the coefficient of kinetic friction, F

_{f}is the frictional force and F

_{N}is normal force between the two surfaces.

Calculation

From the equation, one can derive:

μ

If you have to calculate the coefficient, you need values of the two forces, in units of Newton or Dyne. To calculate the value, all you have to do is substitute those values into the formula and divide to get the answer.

μ

_{Kinetic}= F_{f}/F_{N}If you have to calculate the coefficient, you need values of the two forces, in units of Newton or Dyne. To calculate the value, all you have to do is substitute those values into the formula and divide to get the answer.