JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
The electric field in an electromagnetic wave is given by \(\overrightarrow{\mathrm{E}}=\hat{\mathrm{i}} 40 \cos \omega\left(\mathrm{t}-\frac{\mathrm{z}}{\mathrm{c}}\right) N \mathrm{NC}^{-1}\). The magnetic field induction of this wave is (in SI unit) _______.
- A \(\overrightarrow{\mathrm{B}}=\hat{\mathrm{i}} \frac{40}{\mathrm{c}} \cos \omega\left(\mathrm{t}-\frac{\mathrm{z}}{\mathrm{c}}\right)\)
- B \(\vec{B}=\hat{j} 40 \cos \omega\left(t-\frac{z}{c}\right)\)
- C \(\overrightarrow{\mathrm{B}}=\hat{\mathrm{k}} \frac{40}{\mathrm{c}} \cos \omega\left(\mathrm{t}-\frac{\mathrm{z}}{\mathrm{c}}\right)\)
- D \(\vec{B}=\hat{j} \frac{40}{c} \cos \omega\left(t-\frac{z}{c}\right)\)
Answer & Solution
Correct Answer
(D) \(\vec{B}=\hat{j} \frac{40}{c} \cos \omega\left(t-\frac{z}{c}\right)\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{\mathrm{E}}=\hat{\mathrm{i}} 40 \cos \omega\left(\mathrm{t}-\frac{\mathrm{z}}{\mathrm{c}}\right)\) \(\overrightarrow{\mathrm{E}}\) is along \(+\mathrm{x}\) direction \(\overrightarrow{\mathrm{v}}\) is along \(+\mathrm{z}\) direction So direction of \(\vec{B}\)…
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