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In optical fibers, the Rayleigh scattering is proportional to:

This question was previously asked in
UGC NET Paper 2: Electronic Science 3rd Dec 2021 Shift 2
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  1. \(\frac{1}{\lambda}\)
  2. \(\frac{1}{\lambda^2}\)
  3. \(\frac{1}{\lambda^3}\)
  4. \(\frac{1}{\lambda^4}\)

Answer (Detailed Solution Below)

Option 4 : \(\frac{1}{\lambda^4}\)
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UGC NET Paper 1: Held on 21st August 2024 Shift 1
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Key Points

  • Scattering of light: The phenomenon in which the light ray is redirected in all other directions on passing through particles of dimensions comparable to the wavelength of the light used is called scattering of light.
  • Rayleigh scattering: The scattering of light off of the molecules of the air that can be extended to scattering from particles up to about a tenth of the wavelength of the light used is called Rayleigh scattering.

According to Rayleigh scattering:

\(Intensity\;of\;scattered\;light\;\left( I \right) \propto \;\frac{1}{{{\lambda ^4}}}\)

Where λ is wavelength of light.

So, the correct option is \(\frac{1}{{{\lambda ^4}}}\)

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