Question 133: EM waves

Question

The electric field of a plane electromagnetic
wave is given by
$\overrightarrow E  = {E_0}\widehat i\cos (kz)cos(\omega t)$
The corresponding magnetic field $\overrightarrow B $ is then given by

Accepted Answer

$ 	herefore \overrightarrow E  	imes \overrightarrow B \parallel \overrightarrow v $
Given that wave is propagating along positive z-axis and $\overrightarrow E $ along positive x-axis. Hence $\overrightarrow B $ along y-axis.
From Maxwell equation
$\overrightarrow V  	imes \overrightarrow E  =  - {{\partial B} \over {\partial t}}$
i.e. ${{\partial E} \over {\partial Z}} =  - {{\partial B} \over {dt}}$ and ${B_0} = {{{E_0}} \over C}$

Answer

$\overrightarrow B  = {{{E_0}} \over C}\widehat j\sin (kz)\sin (\omega t)$

Answer

$\overrightarrow B  = {{{E_0}} \over C}\widehat j\sin (kz)\cos (\omega t)$

Answer

$\overrightarrow B  = {{{E_0}} \over C}\widehat j\cos (kz)\sin (\omega t)$

Answer

$\overrightarrow B  = {{{E_0}} \over C}\widehat k\sin (kz)\cos (\omega t)$

EM waves

The electric field of a plane electromagnetic wave is given by \overrightarrow E = {E_0}\widehat i\cos (kz)cos(\omega t) The corresponding magnetic field \overrightarrow B is then given by

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