JEE Mains · Physics · STD 12 - Electromagnetic waves
- JEE Mains 2020
- Easy
- MCQ
If the magnetic field in a plane electromagnetic wave is given by \(\overrightarrow{\mathrm{B}}=3 \times 10^{-8} \sin \left(1.6 \times 10^{3} \mathrm{x}+48 \times 10^{10} \mathrm{t}\right) \hat{\mathrm{j}}\; \mathrm{T}\) then what will be expression for electric field?
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(\overrightarrow{\mathrm{E}}=\left(9 \sin \left(1.6 \times 10^{3} \mathrm{x}+48 \times 10^{10} \mathrm{t}\right) \hat{\mathrm{k}} \;\mathrm{V} / \mathrm{m}\right)\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{\mathrm{E}} \times \overrightarrow{\mathrm{B}}=\overrightarrow{\mathrm{C}}=-\hat{\mathrm{i}}\)
where \(\overrightarrow{\mathrm{B}}\) is along \(\hat{\mathrm{j}}\)
\(\frac{E}{B}=C\)
\(\mathrm{E}=3 \times 10^{-8} \times 3 \times 10^{8}=9 \mathrm{V} / \mathrm{m}\)
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