The interference pattern in this image:
is seen on a screen 1.0m behind an 950 lines/mm diffraction grating.
What is the wavelength of the light? (expressed in nanometers to 2 sig figs)
I know that the equation relating the variables is: d sin(theta)=m(lambda) where theta is the angle from the center maximum to the mth maxima. d being the distance between slits in the grating.
And using the small angle approximation I think you can replace sin(theta) with y/L where y is the distance between the central maximum and the mth one and L is the distance of the screen from the grating
The Attempt at a Solution
I tried plugging the variables into the equation but I can't seem to get the right answer.
lambda=460nm which is wrong
What am I doing wrong?