What is balanced and unbalanced force?

​Balanced forces will cause no change in the speed of an object.

• Balanced forces acting on an object in opposite directions and equal in strength, as shown in the arrows below, do not cause a change in the speed of a moving object.
• Objects that are not moving will not start moving if acted on by balanced forces.

For example, in arm wrestling where there is no winner, the force exerted by each person is equal, but they are pushing in opposite directions. The resulting force (net force) is zero.

Unbalanced forces are not equal, and they always cause the motion of an object to change the speed and/or direction that it is moving.

• When two unbalanced forces are exerted in opposite directions, their combined force is equal to the difference between the two forces.
• The magnitude and direction of the net force affects the resulting motion