Question

If $\overrightarrow{E}$ and $\overrightarrow{B}$ represent electric and magnetic field vectors of the electromagnetic wave, the direction of propagation of electromagnetic wave is along

• A. $\overrightarrow{E}$
• B. $\overrightarrow{B}$
• C. $\overrightarrow{B}\times \overrightarrow{E}$
• D. $\overrightarrow{E}\times \overrightarrow{B}$

Answer 1

The correct option is D $\overrightarrow{E}\times \overrightarrow{B}$

The electric field and the magnetic field of an Electromagnetic wave are mutually perpendicular to each other and their direction of propagation is perpendicular to both the electric and magnetic fields.

If $\overrightarrow{E}$ and $\overrightarrow{B}$ represent electric and magnetic field vectors of electromagnetic wave, then the direction of propagation of electromagnetic wave is along the direction of vector $\overrightarrow{E}\times \overrightarrow{B}$.

The vector product $\overrightarrow{B}\times \overrightarrow{E}$ gives the negative direction of the propagation of wave. So, option $\left(D\right)$ is correct.