Question 42 of 180

Two capacitors of capacities $2C$ and $C$ are joined in parallel and charged up to potential $V.$ The battery is removed and the capacitor of capacity $C$ is filled completely with a medium of dielectric constant $K.$ The potential difference across the capacitors will now be:

A$\dfrac{V}{K+2}$B$\dfrac{V}{K}$C$\dfrac{3V}{K+2}$D$\dfrac{3V}{K}$

Show answer and solution▾

Answer: (C) $\dfrac{3V}{K+2}$

Now,

${V}_{C}=\dfrac{2CV+CV}{KC+2C}$
$=\dfrac{3V}{K+2}$