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