Normal force

The normal force is a contact force that acts perpendicular to the surface of an object in contact with another object. It arises in response to the weight of an object resting on a surface and serves to support that object's weight, preventing it from accelerating through the surface. In a typical scenario, such as a book resting on a table, the gravitational force pulls the book downward, while the table exerts an upward normal force equal in magnitude to the weight of the book.