First slide

Average energy density of electromagnetic wave

Question

The magnetic field in a plane electromagnetic wave is given by $B = (200 μ T) \sin [(4.0 x 10^{15} s^{- 1}) (t - x / c)]$ . Find the average energy density corresponding to the electric field.

Easy

A

$16 x 10^{- 3} J m^{- 3}$
B

$8 x 10^{- 3} J m^{- 3}$
C

$24 x 10^{- 3} J m^{- 3}$
D

$32 x 10^{- 3} J m^{- 3}$

Solution

$\frac{1}{4} \frac{B_{0}^{2}}{μ_{o}} = \frac{1}{4} \times \frac{4 \times 10^{- 8}}{4 π \times 10^{- 7}} = 8 \times 10^{- 3} J m^{- 3}$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App