In optical fibers, the Rayleigh scattering is proportional to:

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In optical fibers, the Rayleigh scattering is proportional to:

30. In optical fibers, the Rayleigh scattering is proportional to:

1. λ

2. 1/λ^2

3.1/λ^3

4.1/λ^4

Answer: D

Solution.

Why Rayleigh Scattering is Proportional to 1/λ⁴

An accelerating charge emits electromagnetic radiation. The radiated power from an oscillating dipole is proportional to the square of its acceleration:

P ∝ a²

If the oscillation frequency is f, then the acceleration scales as:

a ∝ f²

Therefore:

P ∝ f⁴

Convert Frequency to Wavelength

Since:

f = c / λ

substituting into the power relation gives:

P ∝ (1/λ)⁴

P ∝ 1/λ⁴

This is known as the Rayleigh scattering law.

Intuitive Way to Remember

Suppose the wavelength doubles:

λ → 2λ

Then the scattering becomes:

1/(2λ)⁴ = 1/(16λ⁴)

Therefore, doubling the wavelength reduces Rayleigh scattering by 16 times.

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