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Friction comparison: static versus dynamic (kinetic) friction Complete the statement: Static friction is always ______ dynamic friction for the same two surfaces in contact. Choose the correct relation.

Difficulty: Easy

equal to
less than
greater than
unrelated to
depends only on speed

Correct Answer: greater than

Explanation:

Concept/Approach

For a given pair of surfaces, the maximum static friction typically exceeds kinetic (dynamic) friction: μ_s > μ_k. Hence, just before motion, the required force is higher than that needed to keep the body sliding at constant speed.

Final Answer
greater than

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