Q149 / 150 · MHT CET 2026 (20 April Shift 2) · Physics
If charge $+q$ is taken from one point to another over an equipotential surface, then
- Awork done on the charge continuously increases.
- Bwork is done by the charge.
- Cwork done on the charge is constant.
- Correct answerDno work is done.
Solution
The work done in moving a charge $q$ from point $A$ to point $B$ is given by $W = q(V_B - V_A)$.
For an equipotential surface, the electric potential at all points is the same, which means $V_A = V_B$.
Therefore, the potential difference $\Delta V = V_B - V_A = 0$.
Substituting this into the work equation gives $W = q \times 0 = 0$.
Hence, no work is done in moving a charge over an equipotential surface.
Answer: no work is done.
For an equipotential surface, the electric potential at all points is the same, which means $V_A = V_B$.
Therefore, the potential difference $\Delta V = V_B - V_A = 0$.
Substituting this into the work equation gives $W = q \times 0 = 0$.
Hence, no work is done in moving a charge over an equipotential surface.
Answer: no work is done.
Hence, the correct answer is option: 'D'.