A parallel plate capacitor filled with oil of dielectric constant $k = 3$, has a capacitance c. After removing the oil between the plates, the capacitance of the capacitor will become
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → $\frac{1}{3} C$
Capacitance with dielectric: $C = k C_0$, where $C_0$ is capacitance without dielectric
Given: $k = 3$, $C = k C_0 = 3 C_0 \;\Rightarrow\; C_0 = \frac{C}{3}$
Capacitance without dielectric = $C/3$