Question

A Young's double slit apparatus has slits separated by 0.28 mm and a screen 48 cm away from the slits. The whole apparatus is immersed in water and the slits are illuminated by the red light (λ = 700 nm in vacuum). Find the fringe-width of the pattern formed on the screen.

Answer 1

Given that, d = 0.28 mm = 0.28x10^–3 m, D = 48 cm = 0.48 m, λ_a = 700 nm in vacuum