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QJEEM19Ph7ba0: JEE Main 2019 Physics - Class 12 JEEM19Ph7ba0 Solution: The electric field of a plane electromagnetic wave is given by…

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

Step-by-Step Verified Solution

\therefore \overrightarrow E \times \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 \times \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}