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Diffracting grating?kinda confused?

  1. Feb 28, 2009 #1
    Diffracting grating???kinda confused?

    1. The problem statement, all variables and given/known data
    bits given:lamda(660nm) n=1,d=3.33, angle=?


    2. Relevant equations
    n(lambda)=dsin(theta)


    3. The attempt at a solution

    so from re-arranging the formula,etc i got this :6.66x^-7/3.33=sin(theta)
    =>2x10^-7=sin(theta)
    =>angle=1.14x10^-5(after inverse sin function) ? not sure if thats the answer =/
     
  2. jcsd
  3. Feb 28, 2009 #2
    Re: Diffracting grating???kinda confused?

    With what you're given, the answer (in degrees) seems fine to me.

    The Bob
     
  4. Feb 28, 2009 #3
    Re: Diffracting grating???kinda confused?

    k thanks alot cuz some1 told me that i got my d wrong, =) which is not now
     
  5. Feb 28, 2009 #4
    Re: Diffracting grating???kinda confused?

    cant w8 to become astronomer =),need to work hard <.<,good stopped my gaming addiction.sorry if i wasnt allowed to type something out of context
     
  6. Feb 28, 2009 #5
    Re: Diffracting grating???kinda confused?

    As d was stated in the question, I can't see how it can be wrong. Good luck with your studies.

    The Bob
     
  7. Feb 28, 2009 #6

    Redbelly98

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    Re: Diffracting grating???kinda confused?

    What are the units for this value of d? 3.33 meters would be awfully large for a diffraction grating! :eek:
     
  8. Mar 1, 2009 #7
    Re: Diffracting grating???kinda confused?

    in the question was given that a diffraction grating is marked as 300lines/mm
    a)find distance between slits (which i got 3.33 from 1/0.3)
     
  9. Mar 1, 2009 #8
    Re: Diffracting grating???kinda confused?

    lol yea distance between slits 3.33m lol cant be hmm
     
  10. Mar 1, 2009 #9
    Re: Diffracting grating???kinda confused?

    is probably mm
     
  11. Mar 1, 2009 #10
    Re: Diffracting grating???kinda confused?

    I've been away from units for too long. Yer, Redbelly98 is right. If it is 3.33mm then the answer is wrong. I apologise for assuming it was a 'plug-in-the-values' question. What's your final answer?

    The Bob
     
  12. Mar 1, 2009 #11
    Re: Diffracting grating???kinda confused?

    the answer i got is 3.33 for d .idk where i am messing things up.
     
  13. Mar 1, 2009 #12

    Redbelly98

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    Re: Diffracting grating???kinda confused?

    That is the key here. In 1 mm, there are 300 lines. So each line must be ____?
     
  14. Mar 1, 2009 #13
    Re: Diffracting grating???kinda confused?

    hmm would it be: d=1/300000=3.33x10^-6
     
  15. Mar 1, 2009 #14

    Redbelly98

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    Re: Diffracting grating???kinda confused?

    If you include the correct units with that number, yes.
     
  16. Mar 1, 2009 #15
    Re: Diffracting grating???kinda confused?

    k,ty =)
     
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