Diffraction grating

George_H

1. The problem statement, all variables and given/known data

The light shining on a diffraction grating has a wavelength of 488 nm (in vacuum). The grating produces a second-order bright fringe whose position is defined by an angle of 8.02°. How many lines per centimeter does the grating have?


2. Relevant equations

d sin q = nl

3. The attempt at a solution

d = (2)(488)/sin(8.02) = 6995.474955

d = 1/N

N = 1/d = 1/6995.474955 =1.429495505X10^-4 (per M) X 100 = 0.014294955

It got this answer and it is wrong, I have no idea where to go from here or what to do and would be grateful of any help, thanks!

hage567

You should convert the wavelength from nanometers to meters (or cm, whatever). I don't think you did that properly.