NTA Abhyas JEE Main2020PhysicsWave OpticsPractice
In young double slit experiment, the wavelength of red light is 7 8 0 0 Å and that of blue light is 5200 Å The value of n for which n th bright band due to red light coincides with (n + 1) th bright band due to blue light, is :
Options
- A1
- B2
- C3
- D4
Correct answer
B. 2
Step-by-step solution
For bands to coincide n λ 1 D d = n + 1 λ 2 D d ⇒ n 7 8 0 0 = n + 1 5 2 0 0 ⇒ 7 8 n = n + 1 5 2 ⇒ 2 6 n = 5 2 ⇒ n = 2