Work Done by Conservative Force – Rankers Physics

Potential Energy & Equilibrium: Practice Problem & Solution

Assertion (A): Work done by conservative force along closed path is zero. Reason (R): When an object is moved along closed path beginning and ending are at same point its displacement is zero.
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Short Solution (Best for NEET):

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:

Assertion is true by definition of a conservative force, which does zero work over any closed path.

Reason is also true as displacement is zero for a closed path, i.e., \(\Delta \vec{r} = 0\). However, the reason is not the correct explanation for why work by a conservative force is zero; this is due to path independence and \(\Delta U = 0\) for a closed path.

Thus, both are true, but R is not the correct explanation of A.

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