Question

The energy per unit volume of a dielectric medium is proportional to square of

• A. relative permittivity
• B. charge
• C. energy
• D. electric intensity

Answer 1

Answer: (D)

$E=\frac{V}{D}$ volt/meter

$=\frac{D}{k_q{\epsilon }_o}$

$D=q/A$ ………$\left(1\right)$

For energy

$dw=VCdv$

$w=C{\int }_o^{\forall }Vdv=\frac{C{V}^2}{2}=\frac{1}{2}QV$ ……$\left(2\right)$

from equation $\left(1\right)$ & $\left(2\right)$

$W=\frac{ED\cdot dA}{2}$

$\frac{ED\left(volume\right)}{2}$

$\frac{W}{V}\propto E$.