- #1
clockworks204
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1. Light of wavelength 632.8nm is normally incident upon a grating of 5000 lines/cm. How many different diffraction orders can be seen in transmission?
2. m(lambda)=d(sintheta)
3. According to my text, d=1/5000lines/cm = 2x10^-6m
and sintheta= lambda/d = 632.8x10^-9/ 2x10^6 = .3164
If I take sin^-1(.3164), I get 18 degrees.
From here, I don't know what to do because the answer is that 7 beams exist, corresponding to 4 orders, and I don't know how to get to that answer!
2. m(lambda)=d(sintheta)
3. According to my text, d=1/5000lines/cm = 2x10^-6m
and sintheta= lambda/d = 632.8x10^-9/ 2x10^6 = .3164
If I take sin^-1(.3164), I get 18 degrees.
From here, I don't know what to do because the answer is that 7 beams exist, corresponding to 4 orders, and I don't know how to get to that answer!