Question

Define Unbalanced Force ?

Answer 1

An unbalance force is defined as one which is not cancelled by an equal and opposite forces acting on a body. Simply we can say that unbalanced forces produce non-zero net force. And this force changes the direction as well as the rate of motion of a moving body.

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Answer 2

An unbalance force is one that is not opposed by an equal and opposite force operating directly against the force intended to cause a change in the object's state of motion or rest. Take this:

Object, O is at rest and subjected to a force from the left as shown:

Let ====> represent the force to change the object's state of motion or rest on object. O

This unopposed (unbalanced) force will cause the object to move to the right. ====> O

Let O <==== represent an opposing force of equal magnitude operating on object O.

When the forces are opposed and impinging on the object ====> O <====, the object will not move because each force is balanced by an equal and opposite force.

However, if the forces are unbalanced and aligned thus, ====> O <========, the larger force coming from the right is unbalance by the one from the left. So, the object will move toward the left.