Question

Internal force definition and examples

Answer 1

Internal Forces are forces that forces not change the Mechanical energy of an object.
Eg: Gravty, Electrical,Magnetic, Spring.
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i.e. There is always gravitational forces.It does not mean it will change the mechanical energy of an object as there is force acting on it.

​​​​​It doesnot violate the principle of conservation of energy as it can change its form.