COMEDK · Physics · 24. Electromagnetic Waves
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?
- A \(2 \times 10^{-8} \mathrm{~T}\)
- B \(\frac{1}{2} \times 10^{-8} \mathrm{~T}\)
- C \(2 \mathrm{~T}\)
- D \(\frac{1}{2} T\)
Answer & Solution
Correct Answer
(A) \(2 \times 10^{-8} \mathrm{~T}\)
Step-by-step Solution
Detailed explanation
Magnetic field, \(\begin{gathered} B=\frac{E}{c} \text {, where } c=3 \times 10^8 \mathrm{~m} / \mathrm{s} . \\ B=\frac{6}{3 \times 10^8}=2 \times 10^{-8} \mathrm{~T} \end{gathered}\)
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