Question

The capacitance of a capacitor with dielectric medium is $8\mu \text{F}$. On removing the dielectric medium, the capacitance becomes $2\mu \text{F}$. The dielectric constant of the medium is

• A. $1$
• B. $3$
• C. $2$
• D. $4$

Answer 1

The correct option is D $4$

The capacitance with dielectric is given as

$C_{\text{dielectric}}=K{C}_{\text{air}}$

$\Rightarrow C_{\text{air}}=\frac{C_{\text{dielectric}}}{K}$

$\Rightarrow 2=\frac{8}{K}$

$\Rightarrow K=4$