Q 12-08-203JEE MainJEE Main 2019 (8 Apr, Shift 1)Easy
A plane electromagnetic wave travels in free space along the $x$-direction. The electric field component of the wave at a particular point of space and time is $E = 6\ \text{V m}^{-1}$ along $y$-direction. Its corresponding magnetic field component, $B$ would be
Answer: (A) $2\times10^{-8}\ \text{T}$ along $z$-direction
$B = \dfrac Ec = \dfrac{6}{3\times10^8} = 2\times10^{-8}\ \text{T}$. The wave travels along $\vec E\times\vec B$; with $\vec E$ along $y$ and propagation along $x$, $\vec B$ is along $z$ ($\hat j\times\hat k = \hat i$).
Solution by Sreeraj P, M.Sc Physics