Work Done by Friction in Round Trip – Rankers Physics

Potential Energy & Equilibrium: Practice Problem & Solution

Assertion (A): Work done by or against force of friction in moving a body in any round trip is always zero. Reason (R): Frictional force is a conservative force.  
(1) Both (A) & (R) are true and the (R) is the correct explanation of the (A)
(2) Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(3) (A) is true but (R) is false
(4) Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Potential Energy & Equilibrium. Understanding the underlying formula is key to arriving at the correct answer below:

Frictional force is a non-conservative force. Work done by a non-conservative force over a closed path is generally not zero. Therefore, both Assertion and Reason are false.

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