The capacitance of a parallel plate capacitor with air as medium between the plates is 1 nF. When a material of dielectric constant 5 is filled between the plates, the new capacitance becomes-
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 5 nF
Filling the whole gap of a parallel plate capacitor with a dielectric of constant K multiplies its capacitance by K, because \( C = K\varepsilon_0A/d \) while the geometry is unchanged.
\( C' = KC = 5\times1\,\mathrm{nF} = 5\,\mathrm{nF} \)