# Normal force

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, ${\displaystyle \theta }$ would be 0, and so ${\displaystyle cos\theta }$ would be 1. Thus, the two equations are equal.