Posted by Angel on .
A doubleslit interference experiment is performed with light from a laser. The separation between the slits is 0.58 mm, and the
ﬁrstorder 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

Physics 
Elena,
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 
Physics 
Angel,
Excuse me what was the equation you used? Because the answer is wrong.

Physics 
Angel,
And where did you get those numbers?

Physics 
Elena,
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.