# Normal force

FN represents the normal force

Normal force is the force that the ground (or any surface) pushes back up with; If there was no normal force, you would slowly seep into the ground.

The normal force on a object is always perpendicular (at a right angle) to the surface the object is on.

On a flat surface, the normal force of an object is ${\displaystyle mg}$ (the object's weight, that is its mass multiplied by the force of gravity).

On an inclined plane, the normal force is reduced by the angle, and the normal force is ${\displaystyle mgcos\theta }$.

Note that on a flat surface, ${\displaystyle \theta }$ (angle)would be 0, and so ${\displaystyle cos\theta }$ would be 1. Thus, the two equations are equal.