JEE MainPhysicsWave Optics
In an interference pattern produced by two coherent sources of light, the ratio of the difference between the maximum and minimum intensities to their sum is given as 24 25 . The ratio of the maximum amplitude to the minimum amplitude in this interference pattern is
Options
- A16 9
- B4 3
- C7
- D25 7
Correct answer
C. 7
Step-by-step solution
Let the intensities of the two sources be I₁ and I₂ , and their respective amplitudes be A₁ and A₂ . The maximum and minimum intensities are given by: I_ = (A₁ + A₂)^2 I_ = (A₁ - A₂)^2 We are given the ratio: I_ - I_ I_ + I_ = 24 25 Substituting the expressions for I_ and I_ : (A₁ + A₂)^2 - (A₁ - A₂)^2 (A₁ + A₂)^2 + (A₁ - A₂)^2 = 24 25 Simplifying the numerator and denominator: 4A₁ A₂ 2(A₁^2 + A₂^2) = 24 25 2A₁ A₂ A₁^2 + A₂^2 = 24 25 Let the ratio of amplitudes be y = A₁ A₂ . Dividing the numerator and denominator