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NEETPhysicsLaws of Motion

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): When a block of mass m is placed on a rough inclined plane of angle such that Reason (R): The limiting value of static friction is directly proportional to the normal reaction acting on the block. In the light of the above statements, choose the most appropriate answer from the options given below:

Options

  1. ABoth (A) and (R) are correct and (R) is the correct explanation of (A)
  2. BBoth (A) and (R) are correct but (R) is not the correct explanation of (A)
  3. C(A) is correct but (R) is not correct
  4. D(A) is not correct but (R) is correct

Correct answer

B. Both (A) and (R) are correct but (R) is not the correct explanation of (A)

Step-by-step solution

For Assertion (A): The condition For Reason (R): The limiting value of static friction is indeed directly proportional to the normal reaction ( f_ s, max = _s N ). Reason (R) is a correct statement. However, Reason (R) alone does not explain Assertion (A). The correct explanation for (A) is that static friction is a self-adjusting force that balances the applied force ( mg ) when the block is not on the verge of sliding. Therefore, both (A) and (R) are correct but (R) is not the correct explanation of (A). Answer:

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