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Please help with this Physics question?

  1. Apr 18, 2007 #1
    Physics

    If a star has a surface temperature of 1000 degrees Kelvin and emits 500,000 watts of each square-meter of surface area, how much power does each square-meter of its surface area emit after it has cooled to 900 degrees Kelvin?
     
  2. jcsd
  3. Apr 18, 2007 #2

    Hootenanny

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    Welcome to the Forums,

    Have you any thoughts on the question? Which law do you think we should use?
     
  4. Apr 18, 2007 #3
    If a star has a surface temperature of 1000 degrees Kelvin and emits 500,000 watts of each square-meter of surface area, how much power does each square-meter of its surface area emit after it has cooled to 900 degrees Kelvin?
     
  5. Apr 18, 2007 #4
    Stephen-Boltzmann's Law i guess, but i couldn't figure out how? plz help if u have any idea
     
  6. Apr 18, 2007 #5

    Hootenanny

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    Well you could start by writing down the Stephen-Boltzmann law and identifying what all the symbols mean...
     
  7. Apr 18, 2007 #6

    Hootenanny

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    Double posting isn't going to get your thread answered any quicker, I've already answered your other thread.
     
  8. Apr 18, 2007 #7
    Thanks, am a kind of confused.
     
  9. Apr 18, 2007 #8
    it may be easy for u to answer, so plz help me?
     
  10. Apr 18, 2007 #9

    Hootenanny

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    I am trying to help you. The guidelines here at PF prevent us from providing solutions to problems, they also require that you show your efforts and that we guide you through the problem rather than just handing you the solution on a plate.
     
  11. Apr 18, 2007 #10
    ok. this is what i have= v/t=pi*P*D^4/128*L*Visc.

    so 500,000=3.14*100*1000/128*L
    Am i right?
     
  12. Apr 18, 2007 #11

    ZapperZ

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    Two different threads have been merged because the OP made multiple postings.

    Zz.
     
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