Work Done by Electric Field and Centripetal Force – Rankers Physics

Electric Potential: Practice Problem & Solution

Assertion (A): If a point charge be rotated in a circle around another stationary charge at the centre of the circle, the work done by electric field will be zero. Reason (R): Work done by centripetal force is always 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 Electric Potential. Understanding the underlying formula is key to arriving at the correct answer below:

Both (A) and (R) are true. (A) is true because the electric field is conservative and the path is equipotential. (R) is true as centripetal force is perpendicular to displacement (\(W = Fdr\cos 90^\circ = 0\)). However, (R) does not explain (A).

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