The distance between two slits in a double-slit interference experiment is 2.9 x 10-6 m. The first-order bright fringe is measured on a screen at an angle of 12 degrees from the central maximum. What is the wavelength of the light

Answer: λ = 5.41*10^-7 m

Explanation: The formulae that defines a double slit interference experiment is given as

mλ = d*sinθ

from the question,

d = distance between slits = 2.9*10^-6.

m = 1 (since interference occurred at the first order)

θ = 12°

λ=?

By substituting the parameters into the formulae, we have that

1 * λ = 2.9*10^-6 * sin 12°

λ = 2.9*10^-6 * 0.2079

λ = 0.541*10^-6

λ = 5.41*10^-7 m