Question:
A charge is rotated in a circle of radius $r$ around a central charge. The work done is:
A charge is rotated in a circle of radius $r$ around a central charge. The work done is:
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A circular path around a point charge is an equipotential surface; no work is done moving along it.
Updated On: Apr 8, 2026
- Zero
- $qV$
- $V/q$
- $2\pi r q$
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The Correct Option is A
Solution and Explanation
Step 1: Concept
Work done $W = q \Delta V$.
Step 2: Analysis
Potential $V = \frac{1}{4\pi\epsilon_{0}}\frac{q}{r}$. In a circular path around a central charge, the distance $r$ is constant.
Step 3: Conclusion
Since the potential is the same at all points on the circle, $\Delta V = 0$, so $W = 0$.
Final Answer: (A)
Work done $W = q \Delta V$.
Step 2: Analysis
Potential $V = \frac{1}{4\pi\epsilon_{0}}\frac{q}{r}$. In a circular path around a central charge, the distance $r$ is constant.
Step 3: Conclusion
Since the potential is the same at all points on the circle, $\Delta V = 0$, so $W = 0$.
Final Answer: (A)
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