Physics · Static and Kinetic friction, laws of friction, rolling friction

Assertion A body on an inclined plane just tends to slide down if the angle of i

Assertion A body on an inclined plane just tends to slide down if the angle of inclination is equal to angle of friction. Reason When the angle of inclination is equal to the angle of friction, the component of weight parallel to the plane is just sufficient to overcome the frictional force.

  • A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
  • B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
  • C. Assertion is correct but Reason is incorrect
  • D. Both Assertion and Reason are incorrect

Step-by-step solution

The angle of friction is defined such that tan(angle of friction)=coefficient of static friction. When the inclination angle equals the angle of friction, the component of weight parallel to the incline (mg sinθ) equals the maximum static friction (μmg cosθ) because μ=tanθ. This means the body is on the verge of sliding. Therefore, both assertion and reason are correct, and the reason correctly explains the assertion.
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