If the 8th bright band of wavelength $λ_1$ coincides with 9th bright brand of wavelength $λ_2$ in a Young's double slits experiment then the possible wavelength of two lights are:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → $λ_1=450 nm, λ_2=400 nm$
In young's double slit experiment,
$mλ_1=nλ_2$
$⇒8λ_1=9λ_2$
$⇒\frac{λ_1}{λ_2}=\frac{9}{8}$
Now,
$\frac{λ_1}{λ_2}=\frac{450}{400}=\frac{9}{8}$