Question

Coherent light with wavelength 460 nm falls on a pair of slits. On a screen 1.86 m away, the distance between dark fringes is 3.90 mm. What is the slit separation?

Answer 1

Answer:

The split separation d = 2.12 * 10^-4 m

Explanation:

Mathematically, for a double split interference, the relation between separation of slit and fringe width is given by the formula;

d = Rλ/Δy

Where R represents the distance of screen from the slit given as 1.86m , λ is the wavelength of incident light given as 460 nm ,

Δy is the fringe width given as 3.90 nm

plugging these values into the equation, we have;

d = (1.86)(460 * 10^-9)/(3.9 * 10^-3)

d = 2.12 * 10^-4 m