Friction (part-1)

FRICTION

Q.1. What is force? Write few of its characteristics.
Ans.1. A push or a pull on an object is called a force.
                    Force is a vector quantity (having magnitude as well as direction).
          S.I. unit of Force is N (Newton).
          Force can Change the State of Motion.
                Force can Change the Shape of an Object.

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     Q.2. What is friction? 
    Ans.2. The force which opposes the motion of an object on the surface of another object is called force of friction.
Force of friction is a contact force.
The force of friction always opposes the applied force (direction of motion).
 

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