An air capacitor is charged upto a potential `V_1`. It is connected in parallel to an identical uncharged capacitor filled with a dielectric medium. After redistribution of charge if the potential difference of this combination is V, then the dielectric constant of the substance will be

Options

A. `V^(2)(V_(1)-V)`
B. `V(V_(1)-V)`
C. `V/((V_(1)-V))`
D. `((V_(1)-V))/V`

Answer

D

Explanation

`V=(CV_(1))/(C+KC)rArr K=(V_(1)-V)/V`