Question:
A plane electromagnetic wave of frequency $25 \mathrm{GHz}$ is propagating in vacuum along the $z$-direction. At a particular point in space and time, the magnetic field is given by $\vec{B}=5 \times 10^{-8} \hat{j} T$. The corresponding electric field $\vec{E}$ is
(speed of light $c=3 \times 10^{8} \mathrm{~ms}^{-1}$ )
Correct Option: , 4
Solution:
(4) Amplitude of electric field $(E)$ and Magnetic field $(B)$ of an electromagnetic wave are related by the relation
$\Rightarrow E=B c$
$\Rightarrow E=5 \times 10^{-8} \times 3 \times 10^{8}=15 \mathrm{~N} / \mathrm{C}$
$\Rightarrow \vec{E}=15 \hat{i} \mathrm{~V} / \mathrm{m}$