Question

Work done in carrying an electric charge $Q_1$ once round a circle of radius $R$ with a charge $Q_2$ at the centre of the circle:

• A. $\frac{Q_1{Q}_2}{4\pi {\epsilon }_{0}R}$
• B. $\infty$
• C. $\frac{Q_1{Q}_2}{4\pi {\epsilon }_0{R}^2}$
• D. 0

Answer 1

Answer: (D)

0

Work done in moving a charge from A to B $W=\frac{V_{AB}}{Q}$

where $V_{AB}=V_A-V_B$

But here the initial and final positions are same i.e points $A$ and $B$ are same.

$⟹$ $V_A-V_B=0$

$⟹$ $W=0$