Question

If $C$ is the value of the capacitance of a capacitor filled with a given dielectric and $a$ is the capacitance of an identical capacitor in a vacuum, the dielectric constant, symbolized by the Greek letter kappa, , is simply expressed as

• A. $\frac{C}{a}$
• B. None
• C. $\frac{a}{C}$
• D. $C\times a$

Answer 1

Answer: (A)

The capacitance of a parallel plate capacitor filled with the given material of dielectric constant $\kappa$ is given by:

$C=\frac{\kappa {\epsilon }_{0}A}{d}$ .....................eq1

And the capacitance of the same capacitor without the given material is given by:

$a=\frac{{\epsilon }_{0}A}{d}$ .....................eq2

Dividing eq1 by eq2:

$C/a=\kappa$