Parallel Plate Capacitor question from MHT CET 2025 (25 Apr, Shift 2)

Answer: (c)

1. Charge on outer faces $= \frac{q_1 + q_2}{2}$ each; inner faces carry $\pm\frac{q_1 - q_2}{2}$.
2. Only the inner charges make the field between the plates, so effective charge $Q = \frac{q_1 - q_2}{2}$.
3. $V = \frac{Q}{C} = \frac{q_1 - q_2}{2C}$
4. So the answer is (c) $\frac{q_1 - q_2}{2C}$.