Question

A double-slit interference experiment is performed with light from a laser. The separation between the slits is 0.58 mm, and the
first-order maximum of the interference pattern is at an angle of 0.060
◦
from the center of
the pattern.
What is the wavelength of the laser light?
Answer in units of nm

Answer 1

The coordinate of the maximum is
x(max) = k•λ•L/d,
for the first max k=1
x(max1) = λ•L/d,
tanα = x(max1)/L = λ/d.
λ = d• tanα = 0.55•10^-3•1.047•10^-3 = 5.76•10^-7 = 576 nm

Answer 2

Excuse me what was the equation you used? Because the answer is wrong.

Answer 3

And where did you get those numbers?

Answer 4

I've taken 0.55 mm instead of 0.58 mm

If d = 0.55•10^-3, and tan α =1.047•10^-3,
λ = d• tanα = 0.58•10^-3•1.047•10^-3 = 6.07•10^-7 = 607 nm.