NEET 2018 · PhysicsFrictionPrevious Year Question
Which one of the following statements is incorrect?
Answer: (D) The coefficient of sliding friction has the dimensions of length.. Correct Answer (D) Solution: μ = f/N is a ratio of two forces, hence dimensionless — it does NOT have dimensions of length.
- A.Frictional force opposes the relative motion.
- B.The limiting value of static friction is directly proportional to the normal reaction.
- C.Rolling friction is smaller than sliding friction.
- D.The coefficient of sliding friction has the dimensions of length.✓
Correct Answer
(D) The coefficient of sliding friction has the dimensions of length.
Solution & Explanation
Correct Answer (D) Solution: μ = f/N is a ratio of two forces, hence dimensionless — it does NOT have dimensions of length. So (d) is incorrect; (a), (b), (c) are all correct.
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