JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
A plane electromagnetic wave of frequency \(35\ \mathrm{MHz}\) travels in free space along the \(\mathrm{X}\)-direction. At a particular point (in space and time) \(\overrightarrow{\mathrm{E}}=9.6\ \hat{\mathrm{j}} \mathrm{V} / \mathrm{m}\). The value of magnetic field at this point is _______.
- A \(3.2 \times 10^{-8} \ \hat{\mathrm{k}} \mathrm{T}\)
- B \(3.2 \times 10^{-8}\ \hat{\mathrm{i}}\)
- C \(9.6 \ \hat{\mathrm{j}} \mathrm{T}\)
- D \(9.6 \times 10^{-8}\ \hat{\mathrm{kT}}\)
Answer & Solution
Correct Answer
(A) \(3.2 \times 10^{-8} \ \hat{\mathrm{k}} \mathrm{T}\)
Step-by-step Solution
Detailed explanation
\( \frac{E}{B}=C \) \( \frac{E}{B}=3 \times 10^8\) \(B =\frac{E}{3 \times 10^8}=\frac{9.6}{3 \times 10^8} \) \(B =3.2 \times 10^{-8} \mathrm{~T} \) \(\hat{B} =\hat{v} \times \hat{E} \) \( =\hat{i} \times \hat{j}=\hat{k}\) So,…
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