Force:

It is the force that enables us to do any work.

To do anything, either we pull or push the object. Therefore, pull or push is called force.

Example: to open a door, either we push or pull it. A drawer is pulled to open and pushed to close.

Effect of Force:

Force can make a stationary body in motion. For example a football can be set to move by kicking it, i.e. by applying a force.

Force can stop a moving body: For example by applying brakes, a running cycle or a running vehicle can be stopped.

Force can change the direction of a moving object. For example; By applying force, i.e. by moving handle the direction of a running bicycle can be changed. Similarly by moving steering the direction of a running vehicle is changed.

Force can change the speed of a moving body: By accelerating, the speed of a running vehicle can be increased or by applying brakes the speed of a running vehicle can be decreased.

Force can change the shape and size of an object. For example: By hammering, a block of metal can be turned into a thin sheet. By hammering a stone can be broken into pieces.