If → E and → K represent electric field and propagation vectors of...

If $\overset{\to}{E}$ and $\overset{\to}{K}$ represent electric field and propagation vectors of the EM waves in vacuum, then magnetic field vector is given by:

( $\omega -$ angular frequency)

If → E and → K represent electric field and propagation vectors of the EM waves in vacuum, then magnetic field vector

Options

A $\dfrac{1}{\omega}\left(\overset{\to}{K} \times \overset{\to}{E}\right)$
B $\omega\left(\overset{\to}{E} \times \overset{\to}{K}\right)$
C $\omega\left(\overset{\to}{K} \times \overset{\to}{E}\right)$
D $\overset{\to}{K} \times \overset{\to}{E}$

Correct answer

A. $\dfrac{1}{\omega}\left(\overset{\to}{K} \times \overset{\to}{E}\right)$

Step-by-step solution

As we know, direction of electromagnetic wave will be in the direction of the vector $\overset{\to}{E} \times \overset{\to}{B}$ .

If → E and → K represent electric field and propagation vectors of the EM waves in vacuum, then magnetic field vector

Magnitude of $B = \dfrac{E}{c} = \dfrac{K}{\omega}E$

$⇒ \overset{\to}{B} = \dfrac{1}{\omega}\left(\overset{\to}{K} \times \overset{\to}{E}\right)$

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