Answer
$ε_{r} = 5.52$
Work Step by Step
Given:
Polarization, P, of a dielectric material positioned within a parallel-plate capacitor is to be $4.0 \times 10^{-6} C/m^{2}$.
Required:
dielectric constant if an electric field of $10^{5} V/m$ is applied.
Solution:
Using Equation 18.32:
$ε_{r} = \frac{P}{ε_{0}E} + 1 = \frac{(4.0 \times 10^{-6} C/m^{2})}{(8.85 \times 10^{-12} F/m) (10^{5} V/m)} + 1 = 5.52$