An unbalanced force is created when there are two force that are pulling on the object with different forces therefore the object will result in moving. An example of an unbalanced force is a basketball , when the person pushes down on the ball  they are using more force than gravity therefore it is  moving (a result of an unbalanced force).

Balanced and Unbalanced Forces

This is an unbalanced force because the two people are pulling with different amount of force.

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