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Electromagnetic Waves — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsElectromagnetic Waves1 Mark
MCQ
An electromagnetic wave going through vacuum is described by $\text{E}=\text{E}_0\sin(\text{kx}-    \omega\text{t});\text{B}=\text{B}_0\sin(\text{kx}- \omega\text{t}).$ Which of the following equation is true?
  • ✓
    $\text{E}_0\text{k}=\text{B}_0\omega$
  • B
    $\text{E}_0\omega=\text{B}_0\text{k}$
  • C
    $\text{E}_0\text{B}_0=\omega\text{k}$
  • D
    None of the above
✓

Answer

Correct option: A.
$\text{E}_0\text{k}=\text{B}_0\omega$
$\frac{\text{E}_0}{\text{B}_0}=\text{c},$ also $\frac{2\pi}{\lambda}$ and $\omega=2\pi\text{v}.$
$\Rightarrow\frac{\text{E}_0}{\text{B}_0}=\frac{\omega}{\text{k}}$
$\text{E}_0\text{k}=\text{B}_0\omega$

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