JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
If \(\vec{E}\) and \(\vec{K}\) represent electric field and propagation vectors of the EM waves in vacuum, then magnetic field vector is given by : \((\omega-\) angular frequency) :
- A \(\frac{1}{\omega}(\overrightarrow{ K } \times \overrightarrow{ E })\)
- B \(\omega(\vec{E} \times \vec{K})\)
- C \(\omega(\overrightarrow{ K } \times \overrightarrow{ E })\)
- D \(\overrightarrow{ K } \times \overrightarrow{ E }\)
Answer & Solution
Correct Answer
(A) \(\frac{1}{\omega}(\overrightarrow{ K } \times \overrightarrow{ E })\)
Step-by-step Solution
Detailed explanation
Magnetic field vector will be in the direction of \(\hat{ K } \times \hat{ E }\) magnitude of \(B =\frac{ E }{ C }=\frac{ K }{\omega} E\) Or \(\overrightarrow{ B }=\frac{1}{\omega}(\overrightarrow{ K } \times \overrightarrow{ E })\)
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