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JEE Main20208 Jan 2020Morning ShiftPhysicsRay OpticsActual

The critical angle of a medium for a specific wavelength, if the medium has relative permittivity 3 and relative permeability 4 3 for this wavelength, will be:

Options

  1. A15 o
  2. B30 o
  3. C45 o
  4. D60 o

Correct answer

B. 30 o

Step-by-step solution

V = 1 μ ε n = μ r ε r = 2 s i n   i c = 1 n = 1 2 i c = 30 °

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