JEE Mains · Physics · STD 12 - 8. Electromagnetic waves
If electric field intensity of a uniform plane electro magnetic wave is given as \(E =-301.6 \sin ( kz -\omega t ) \hat{a}_{ x }+452.4 \sin ( kz -\omega t )\) \(\hat{a}_{y} \frac{V}{m}\) Then, magnetic intensity \(H\) of this wave in \(Am ^{-1}\) will be [Given: Speed of light in vacuum \(c =3 \times 10^{8} ms ^{-1}\), permeability of vacuum \(\mu_{0}=4 \pi \times 10^{-7} NA ^{-2}\) ]
- A \(+0.8 \sin ( kz -\omega t ) \hat{ a }_{ y }+0.8 \sin ( kz -\omega t ) \hat{ a }_{ x }\)
- B \(+1.0 \times 10^{-6} \sin ( kz -\omega t ) \hat{ a }_{ y }+1.5 \times 10^{-6}( kz -\omega t ) \hat{ a }_{ x }\)
- C \(-0.8 \sin ( kz -\omega t ) \hat{ a }_{ y }-1.2 \sin ( kz -\omega t ) \hat{ a }_{ x }\)
- D \(-1.0 \times 10^{-6} \sin ( kz -\omega t ) \hat{ a }_{ y }-1.5 \times 10^{-6} \sin ( kz -\omega t ) \hat{ a }_{ x }\)
Answer & Solution
Correct Answer
(C) \(-0.8 \sin ( kz -\omega t ) \hat{ a }_{ y }-1.2 \sin ( kz -\omega t ) \hat{ a }_{ x }\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{ E }=301.6 \sin ( kz -\omega t )\left(-\hat{ a }_{ x }\right)+452.4 \sin ( kz -\omega t ) \hat{ a }_{ y }\)…
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