A plane electromagnetic wave of frequency 50 MHz travels in free space along the x-direction. If at a particular point in space and time, $\vec E=(9.3\hat j)Vm^{-1}$, what is $\vec B$ at this point?

$(3.1 × 10^{-8}\hat k) T$

The correct answer is Option (4) → $(3.1 × 10^{-8}\hat k) T$

The relationship between the electric field (E) and the Magnetic field (B).

$B=\frac{1}{C}\hat k×E$

$=\frac{1}{C}(\hat i×9.3\hat j)=\frac{9.3}{C}(\hat i×\hat j)$

$=\frac{9.3}{3×10^8}\hat k$

$=3.1×10^{-8}T\hat k$