Question

The work done in carrying a charge $q$ once round a circle of radius $r$ with a charge $Q$ at the centre is :

• A. $\frac{q Q }{ 4 \pi \varepsilon_0 r}$
• B. $\frac{q Q }{ 4 \pi \varepsilon_0^2 r^2}$
• C. $\frac{q Q }{ 4 \pi \varepsilon_0 r^2}$
• D. none of the above

Answer 1

Answer: (D)

none of the above

Answer 2

The potential at each point on the circular path will be equal.
So, work done = $q \times$ potential difference
$= q \times O$
$= 0$