Question

An electromagnetic wave in vacuum has the electric and magnetic field $\overrightarrow{E}$ and $\overrightarrow{B}$, which are always perpendicular to each other. The direction of polarization is given by $\overrightarrow{X}$ and that of wave propagation by $\overrightarrow{k}$. Then

• A. $\overrightarrow{X}||\overrightarrow{B}and\overrightarrow{k}||\overrightarrow{B}\times \overrightarrow{E}$
• B. $\overrightarrow{X}||\overrightarrow{B}and\overrightarrow{k}||\overrightarrow{B}\times \overrightarrow{B}$
• C. $\overrightarrow{X}||\overrightarrow{B}and\overrightarrow{k}||\overrightarrow{E}\times \overrightarrow{B}$
• D. $\overrightarrow{X}||\overrightarrow{E}and\overrightarrow{k}||\overrightarrow{B}\times \overrightarrow{E}$

Answer 1

The correct option is D

$\overrightarrow{X}||\overrightarrow{E}and\overrightarrow{k}||\overrightarrow{B}\times \overrightarrow{E}$

The direction of polarization is in $\overrightarrow{E}$ direction and direction of propagation is in $\overrightarrow{E}X\overrightarrow{B}$ direction.