The figure shows two parallel equipotential surfaces $A$ and $B$ kept a small distance $r$ apart from each other. $A$ point charge of $q$ coulomb is taken from the surface $A$ to $B$. The amount of net work done will be
The figure shows two parallel equipotential surfaces $A$ and $B$ kept a small distance $r$ apart from each other. $A$ point charge of $q$ coulomb is taken from the surface $A$ to $B$. The amount of net work done will be
- A
$ - \frac{1}{{4\pi {\varepsilon _0}}}\frac{q}{r}$
- B
$ \frac{1}{{4\pi {\varepsilon _0}}}\frac{q}{r^2}$
- C
$- \frac{1}{{4\pi {\varepsilon _0}}}\frac{q}{r^2}$
- D
Zero
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