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8. Electromagnetic waves — Physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 SciencePhysics8. Electromagnetic waves1 Mark
MCQ
In an electromagnetic wave the electric field vector and magnetic field vector are given as $\vec{E}=E_{0} \hat{i}$ and $\vec{B}=B_{0} \hat{k}$ respectively. The direction of propagation of electromagnetic wave is along.
  • A
    $\hat{j}$
  • B
    $(\hat{k})$
  • C
    $(-\hat{k})$
  • ✓
    $(-\hat{j})$
✓

Answer

Correct option: D.
$(-\hat{j})$
d
Direct of propagation $=\vec{E} \times \vec{B}=\hat{i} \times \hat{k}=-\hat{j}$

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