A plane electromagnetic wave of frequency $35 \mathrm{~MHz}$ travels in free space along the $X$-direction. At a particular point (in space and time) $\vec{E}=9.6 \hat{j} \mathrm{~V} / \mathrm{m}$. The value of magnetic field at this point is :
Solution
<p>$$\begin{aligned}
\frac{E}{B} & =C \\
\frac{E}{B} & =3 \times 10^8 \\
B & =\frac{E}{3 \times 10^8}=\frac{9.6}{3 \times 10^8} \\
B & =3.2 \times 10^{-8} T \\
\hat{B} & =\hat{v} \times \hat{E} \\
& =\hat{i} \times \hat{j}=\hat{k}
\end{aligned}$$</p>
<p>So,</p>
<p>$\overrightarrow{\mathrm{B}}=3.2 \times 10^{-8} \hat{\mathrm{k}} \mathrm{T}$</p>
About this question
Subject: Physics · Chapter: Electromagnetic Waves · Topic: Properties of EM Waves
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