JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
A plane electromagnetic wave of frequency \(100\, MHz\) is travelling in vacuum along the \(x -\) direction. At a particular point in space and time, \(\overrightarrow{ B }=2.0 \times 10^{-8} \hat{ k } T\). (where, \(\hat{ k }\) is unit vector along \(z-\)direction) What is \(\overrightarrow{ E }\) at this point ?
- A \(0.6 \hat{j}\, V / m\)
- B \(6.0 \hat{ k }\, V / m\)
- C \(6.0 \hat{ j }\, V / m\)
- D \(0.6 \hat{ k }\, V / m\)
Answer & Solution
Correct Answer
(C) \(6.0 \hat{ j }\, V / m\)
Step-by-step Solution
Detailed explanation
\(E = BC =6\) (Dir. of wave) \(\|(\overrightarrow{ E } \times \overrightarrow{ B })\) \(\hat{ i }=\hat{ j } \times \hat{ k }\) \(\overrightarrow{ E }=6 \hat{ j } V / m\)
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