MHT CET202519 Apr 2025Morning ShiftPhysicsWave OpticsActual
In Young's double slit interference experiment, using two coherent sources of different amplitudes, the intensity ratio between bright to dark fringes is 5: 1 . The value of the ratio of resultant amplitudes of bright fringe to dark fringe is
Options
- A( 5 +1 5 -1 )
- B5 : 1
- C( 5 -1 5 +1 )
- D1: 5
Correct answer
B. 5 : 1
Step-by-step solution
In Young's double-slit experiment, the intensity ratio between bright and dark fringes is given as 5:1 . Since intensity is proportional to the square of amplitude, we have I_ max I_ min = 5 = ( A₁ + A₂ A₁ - A₂ )^2 . Taking the square root of both sides yields A₁ + A₂ A₁ - A₂ = 5 . This expression equals the ratio of resultant amplitudes at bright and dark fringes, A_ bright A_ dark . The amplitude ratio is therefore 5 :1 .