Question

Determine the slit width that produces a diffraction pattern with the 2nd dark fringe at 6.2mm from the central fringe. The screen distance is 1.25m and the light wavelength is 600nm.

Answer 1

Answer:

d= 0.242 mm

Explanation:

Slit width (d ) = ?

Screen distance ( D ) = 1.25 m

Wave length of light λ = 600 nm

Distance of n the dark fringe from centre

= n λ D / d

Here n = 2

so

$6.2\times10^{-3}=\frac{2\times600\times10^{-9}}{d}$

$d=\frac{1500\times10^{-6}}{6.2}$

d= 0.242 mm