- Joined
- May 23, 2014
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Conceptual: How does the spreading of a bright spot on a screen reduce the chance that all slits of a diffraction grating are interfering constructively?
Another Ques: A diffraction grating with 8000 lines/cm is illuminated with white light. What is the spectrum of the HIGHEST order that includes any portion of the visible spectrum?
Answer is 3.
m=(dsintheta)/wavelength
d=1/8000 lines/cm.
m=[(1/8000) x 10^-2 m/line]/400 nm=3
Ok, I don't understand why you would set d as the reciprocal of 8000 lines/cm. And isnt there a problem with the units on 10^-2 m/line? I thought it was supposed to be 8000 lines/cm or 1 cm per 1/8000 lines? Or is the above d= 1/8000 lines/cm in correct, but should be 1/8000 cm/line since taking the reciprocal would flip the units as well.
Another Ques: A diffraction grating with 8000 lines/cm is illuminated with white light. What is the spectrum of the HIGHEST order that includes any portion of the visible spectrum?
Answer is 3.
m=(dsintheta)/wavelength
d=1/8000 lines/cm.
m=[(1/8000) x 10^-2 m/line]/400 nm=3
Ok, I don't understand why you would set d as the reciprocal of 8000 lines/cm. And isnt there a problem with the units on 10^-2 m/line? I thought it was supposed to be 8000 lines/cm or 1 cm per 1/8000 lines? Or is the above d= 1/8000 lines/cm in correct, but should be 1/8000 cm/line since taking the reciprocal would flip the units as well.
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