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Electromagnetic Waves — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsElectromagnetic Waves3 Marks
Question
A plane electromagnetic wave travels in vacuum, along the Y-direction. Write down the:
  1. Ratio of the magnitudes,
  2. The direction, of its electric and magnetic field vectors.
✓

Answer

  1. $\frac{\text{B}}{\text{E}}=$ speed of light (c = 3 × 108m/ s),

  2. $\vec{\text{K}},\vec{\text{E}},\vec{\text{B}}$ form a right handed system. As wave propagation vector $(\vec{\text{K}})$ is along Y-axis; electric field $(\vec{\text{E}})$ must be along Z-axis and magnetic field $\vec{\text{B}}$ along X-axis.

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