5 Laws of Friction - Class 11 Physics - Laws of motion

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5 Laws of Friction  - Class 11 Physics - Laws of motion 

Laws of friction are stated as : 

1. The direction of the limiting force of friction is always opposite to the direction in which the motion of a body takes place or tends to take place.

2. The force of friction acts tangentially along the surfaces of contact of two bodies.

3. The magnitude of the limiting force of friction (f) is directly proportional to the normal reaction (R) between the two surfaces , that is , $f \propto R$ 

4. Limiting force of friction is independent of the area of the surfaces of contact of two bodies as long as normal reaction is constant.

5. Limiting force of friction depends on the nature of the surfaces in contact.

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