Do electromagnetic waves fade with distance in vacuum?

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SUMMARY

Electromagnetic (EM) waves produced by accelerating charged particles do fade with distance due to the inverse square law, which states that energy density decreases as the wave propagates over a growing spherical surface. However, the frequency of the EM wave remains constant regardless of distance. Despite the fading of signals, astronomers can detect these waves from outer space because they begin with significant energy, allowing enough to reach telescopes even after traveling vast distances.

PREREQUISITES
  • Understanding of electromagnetic wave propagation
  • Familiarity with the inverse square law
  • Basic knowledge of frequency and energy concepts
  • Awareness of astronomical signal detection methods
NEXT STEPS
  • Research the inverse square law in detail
  • Explore the principles of electromagnetic wave propagation
  • Study the methods used in astronomical signal detection
  • Investigate the relationship between energy and frequency in EM waves
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Astronomers, physicists, and students interested in electromagnetic theory and signal detection from space.

yashraj
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TL;DR
Do electromagnetic wave gets weaker with the increasing distance from the source in its travel ?
I want to know that when a charged particle accelerates then the electromagnetic wave so produced will loose it's strength or can say fades with distance or not ? If yes then what happens to its frequency and also tell me if electromagnetic waves fades away with increasing distance from the source then how physicists detects signals from the outer space which have travelled thousands of light years ?
 
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Welcome to PF.

As an EM wave radiates out into space, the energy is distributed over the surface of a radially growing sphere. That causes the EM wave energy density to be reduced by the inverse square law.

The frequency of the EM wave remains the same.

The signals detected from space start out with incredible energy. After the inverse square law has been applied, there is sufficient energy remaining, to enter the aperture of the telescope, and for the signals to be detected.
 
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Baluncore said:
Welcome to PF.

As an EM wave radiates out into space, the energy is distributed over the surface of a radially growing sphere. That causes the EM wave to be reduced by the inverse square law.

The frequency of the EM wave remains the same.

The signals detected from space start out with incredible energy. After the inverse square law has been applied, there is sufficient energy remaining, to enter the aperture of the telescope, and for the signals to be detected.
Thank you for the answer. I was actually thinking almost same but I wanted to make sure that I was right.
 
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