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Basic definition check: Coefficient of friction equals limiting friction divided by normal reaction. Assess the statement's correctness for dry (Coulomb) friction.

Difficulty: Easy

True
False
True only for static friction, not kinetic
Cannot be concluded

Correct Answer: True

Explanation:

Concept/Approach

The (static) coefficient of friction μ_s is defined at impending motion: μ_s = F_limiting / N.
The kinetic coefficient μ_k is similarly defined with kinetic friction: μ_k = F_k / N.

Conclusion
The statement matches the standard definition of coefficient of friction (limiting friction/normal reaction for static). Hence it is True.

Common pitfall
Confusing the definition (a ratio) with a particular measured value; μ is material-pair dependent and dimensionless.

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