Yes, in most cases, when two objects are in physical contact, there is an interaction between them that involves the application of a normal force. The normal force is a fundamental concept in classical mechanics and is one of the fundamental forces that govern interactions between objects at the macroscopic level.

The normal force is a contact force exerted by a surface to support the weight of an object resting on it. It acts perpendicular to the surface and prevents objects from passing through each other. When an object is placed on a surface, such as a table or a floor, the surface pushes back against the object with a force that counters the force of gravity pulling the object downward.

For example, when you place a book on a table, the table exerts an upward normal force on the book, which balances the downward force due to gravity. Without the normal force, objects would simply fall through surfaces, and stable structures like buildings wouldn't be possible.

However, there are scenarios in which the normal force might not be present or might not be the only force at play. For instance, in situations involving sliding or friction between surfaces, the normal force might be accompanied by other forces like friction or tension. Additionally, at very small scales or in certain exotic physical conditions, the behavior of objects and forces can deviate from classical mechanics.