What are Contact Forces? Contact Forces means that a force arises on an object because it is in physical contact with another object. Neglecting electromagnetic interactions, all the forces dealt with in mechanics are contact forces except for the Gravitational Force. Centripetal Force arises from other forces and hence can be created by both contact and non-contact forces.

Examples of Contact Forces:

Here is an example...

In this diagram, there are many forces acting. Can you draw a free body diagram for each mass ? Try it
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