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Suppose that there is a dispersive medium whose refractive index depends on the wavelength as given by \(n(λ) = n_0 +\frac{ a}{λ^2}-\frac{b}{λ^4}\) . The value of 𝜆 at which the group and phase velocities would be the same, is:
Suppose that there is a dispersive medium whose refractive index depends on the wavelength as given by \(n(λ) = n_0 +\frac{ a}{λ^2}-\frac{b}{λ^4}\) . The value of 𝜆 at which the group and phase velocities would be the same, is:
Updated On: Oct 1, 2024
- \(\sqrt\frac{2a}{a}\)
- \(\sqrt\frac{b}{2a}\)
- \(\sqrt\frac{3b}{a}\)
- \(\sqrt\frac{b}{3a}\)
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The Correct Option is A
Solution and Explanation
The correct option is (A): \(\sqrt\frac{2a}{a}\)
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