Correct Answer - Option 1 : Only a is correct
CONCEPT:
Friction:
- The resistance offered by the surfaces that are in contact with each other when they move over each other is called friction.
- Factors affecting friction:
- Types of surfaces in contact.
- The normal force between the two surfaces.
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The friction force between any two surfaces is given as,
⇒ F = μN
Where F = friction force, μ = co-efficient of friction, N = normal reaction and m = mass of the body
- The friction force between any two surfaces is independent of the surface area.
EXPLANATION:
- The friction force between any two surfaces is given as,
⇒ F = μN -----(1)
- The normal reaction when the applied force is horizontal is given as,
⇒ N = mg -----(2)
Where F = friction force, μ = co-efficient of friction, N = normal reaction and m = mass of the body
By equation 1 and equation 2,
⇒ F = μmg -----(3)
- The friction force between any two surfaces is independent of the surface area.
- By equation 3 it is clear that the friction force depends on the weight of the body.
- Hence, option 1 is correct.