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Question
Answer in short.
State the laws of static friction.
Solution
- First law: The limiting force of static friction (FL) is directly proportional to the normal reaction (N) between the two surfaces in contact.
FL ∝ N
∴ FL = μS N
where, μS = constant called the coefficient of static friction. - Second law: The limiting force of friction is independent of the apparent area between the surfaces in contact, so long as the normal reaction remains the same.
- Third law: The limiting force of friction depends upon materials in contact and the nature of their surfaces.
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