NEETPhysicsWave Optics
Two separate Young's double slit experiments are performed. In the first experiment, light of wavelength 500 nm is used with a slit separation d and screen distance D . In the second experiment, light of wavelength 600 nm is used with a slit separation d 2 and screen distance 2D . The ratio of the fringe width in the first experiment to that in the second experiment is
Options
- A5 : 24
- B24 : 5
- C5 : 6
- D5 : 12
Correct answer
A. 5 : 24
Step-by-step solution
Fringe width in a Young's double slit experiment is given by = D d . For the first experiment: ₁ = ₁ D₁ d₁ = 500 nm D d For the second experiment: ₂ = ₂ D₂ d₂ = 600 nm (2D) ( d 2 ) = 2400 nm D d Taking the ratio of the two fringe widths: ₁ ₂ = ( 500 D d ) ( 2400 D d ) = 500 2400 = 5 24 Thus, the ratio is 5 : 24 . Answer: 5 : 24