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12.7: Antenna Systems (Summary)

Last updated

Oct 5, 2024
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- 12.6: Standing Waves and Resonance
- 13: Propagation of Electromagnetic Waves

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Key Terms

transverse wave	a wave, such as an electromagnetic wave, which oscillates perpendicular to the axis along the line of travel
standing wave	a wave that oscillates in place, with nodes where no motion happens
wavelength	the distance from one peak to the next in a wave
amplitude	the height, or magnitude, of an electromagnetic wave
frequency	the number of complete wave cycles (up-down-up) passing a given point within one second (cycles/second)
resonant system	a system that displays enhanced oscillation when subjected to a periodic disturbance of the same frequency as its natural frequency
oscillate	to fluctuate back and forth in a steady beat

Summary

Production of Electromagnetic Waves

Electromagnetic waves are created by oscillating charges (which radiate whenever accelerated) and have the same frequency as the oscillation.
Since the electric and magnetic fields in most electromagnetic waves are perpendicular to the direction in which the wave moves, it is ordinarily a transverse wave.
The strengths of the electric and magnetic parts of the wave are related by $\frac{E}{B} = c, \nonumber$ which implies that the magnetic field $B$ is very weak relative to the electric field $E$ .

Key Terms

Summary

Production of Electromagnetic Waves

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