Question
- How are electromagnetic waves produced? Explain.
- A plane electromagnetic wave is travelling through a medium along the +ve z-direction. Depict the electromagnetic wave showing the directions of the oscillating electric and magnetic fields.
✓
Answer
- Electromagnetic waves are formed as a result of accelerating (electric) charges under electric field. Electric charge exhibit electrostatic behaviour and once they start moving magnetic effects come into play. As a result of this a duality is established which is called electromagnetism. The electromagnetic waves are emitted by those charged particles. These waves move with the velocity of light
- The cross product of electric and magnetic field vectors i.e.$\vec{E}\times\vec{B}$ gives the direction in which the wave travels.
The propagation of electromagnetic wave in +z direction is shown here:
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