Explain contact and non-contact forces.

Explanation

Force : Force is defined as a push or pull acting on a body.
The force which come in play only when two objects come in contact with each other are called contact forces. Some contact forces are :
Muscles force : The forces resulting due to the action of muscles are known as muscular forces. Muscular force is a contact force because it comes in play when two bodies come in contact with each other.
Force of friction : When a body is moving, then a force in opposite direction of motion is exerted on that moving body. This force is called force of friction. It is also a contact force because it is exerted when two surfaces come in contact with each other.
The forces which can be exerted from a distance, without establishing a contact are called non-contact forces. Some non-contact forces are :
Magnetic force : The force exerted by a magnet on other magnet or some other magnetic substances like iron is called magnetic force. Like poles of a magnet repel each other and unlike poles of a magnet attract each other without contact. So it is called non-contact force.
Electrostatic force : The force exerted by a charged body on other charged or uncharged body is called electrostatic force. Electrostatic force also acts without making a direct contact with other charged or uncharged body. So it is also a non-contact force.
Force of gravity : Earth pulls every thing or body towards it. The force of attraction exerted by earth on any object is called force of gravity. This is also a non-contact force as it acts from a distance.