Stress acting perpendicular to an imaginary plane cutting through an object. Normal stress has two senses: compression and tension. Normal stress is often simply called stress. Pin connection: In two dimensions, a pin connection restrains two translation degrees of freedom but does not restrain rotation. Since the rotation degree of freedom is unrestrained at a pin connection, it transfers no moment.

The force per unit area on a given plane within a body a = F/A

That stress component perpendicular to a given plane. If you lean against a door after you close it, you are applying normal stress to the door. ( See also shear stress.)

A stress which acts at right angles to a plane in the interior of a body.