The mean electric energy density between the plates of a charged capacitor is (here q= charge on the capacitor and A= area of the capacitor plate)

Question

The mean electric energy density between the plates of a charged capacitor is (here q= charge on the capacitor and A= area of the capacitor plate) (A) (q2/2 ε0 A2) (B) (q/2 ε0 A2) (C) (q2/2 ε0 A) (D) None of the above

Tardigrade Admin · Accepted Answer

Energy density =(1/2) ε0 E2=(1/2) ε0((σ/ε0))2 =(σ2/2 ε0)=(q2/2 ε0 A2)

Q. The mean electric energy density between the plates of a charged capacitor is (here $q =$ charge on the capacitor and $A =$ area of the capacitor plate)

$\frac{q ^{2}}{2 ε _{0} A ^{2}}$

$\frac{q}{2 ε _{0} A ^{2}}$

$\frac{q ^{2}}{2 ε _{0} A}$

None of the above

Energy density
$= \frac{1}{2} ε_{0} E^{2} = \frac{1}{2} ε_{0} (\frac{σ}{ε _{0}})^{2}$
$= \frac{σ ^{2}}{2 ε _{0}} = \frac{q ^{2}}{2 ε _{0} A ^{2}}$

Q. The mean electric energy density between the plates of a charged capacitor is (here q= charge on the capacitor and A= area of the capacitor plate)

2ε0​A2q2​

2ε0​A2q​

2ε0​Aq2​