NEET Physics EM Waves NEET PYQ-EM Waves

An em wave is propagating in a medium with a velocity \[\overrightarrow{\text{v}}=\text{v}\widehat{\text{i}}\]. The instantaneous oscillating electric field of this em wave is along \[\text{+y}\] axis. Then the direction of oscillating magnetic field of the em wave will be along                                                                                [NEET - 2018]

A) -y direction

B)      +z direction

C)   -z direction

D) -x direction

Correct Answer: B

Solution :

[b] \[\overrightarrow{\text{E}}\times \overrightarrow{\text{B}}=\overrightarrow{\text{V}}\]

\[(\text{E}\overrightarrow{\text{j}})\times (\overrightarrow{\text{B}})=\text{v}\widehat{\text{i}}\]

So, \[\overrightarrow{\text{B}}\text{=B}\widehat{\text{k}}\]

Direction of propagation is along +z direction.