Q163 / 180 · COMEDK 2023 (Memory Based) · Physics
A plane electromagnetic wave of frequency $20 \mathrm{MHz}$ travels through a space along $x$-direction. If the electric field vector at a certain point in space is $6 \mathrm{Vm}^{-1}$, then what is the magnetic field vector at that point?
- Correct answerA$2 \times 10^{-8} \mathrm{~T}$
- B$\frac{1}{2} \times 10^{-8} \mathrm{~T}$
- C$2 \mathrm{~T}$
- D$\frac{1}{2} T$
Solution
Magnetic field,
$\begin{gathered}
B=\frac{E}{c} \text {, where } c=3 \times 10^8 \mathrm{~m} / \mathrm{s} . \\
B=\frac{6}{3 \times 10^8}=2 \times 10^{-8} \mathrm{~T}
\end{gathered}$
Hence, the correct answer is option: 'A'.