→ 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.

Effects of Force

→ Force can make a stationary body in object.

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.