Consider the figure as shown below. If work done in bringing a point charge from infinity to points A, B and C are $W_A, W_B$ and $W_C$, respectively, then, which of the following relation is correct? |
$W_A < W_B < W_C$ $W_A > W_B > W_C$ $W_A = W_B = W_C$ $W_A > W_B < W_C$ |
$W_A = W_B = W_C$ |
The correct answer is Option (3) → $W_A = W_B = W_C$ Points A, B, C are at the same distance $r$ from the charge $q$ (on the same circular arc). Electric potential at each point: $V=\frac{1}{4\pi\varepsilon_0}\frac{q}{r}$ (same $r$). Work to bring a test charge $q_t$ from infinity: $W=q_tV$ (same for all three points). Therefore: $W_A = W_B = W_C$ |