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Light intensity question?

  1. Sep 18, 2008 #1
    1. The problem statement, all variables and given/known data
    For a science project, you would like to horizontally suspend an 8.5 by 11 inch sheet of black paper in a vertical beam of light whose dimensions exactly match the paper.

    If the mass of the sheet is 1.0 g, what light intensity will you need?

    2. Relevant equations

    Equation I used: F = IA/c


    3. The attempt at a solution

    F = 9.8x10^-3 N
    A = 6.03 m^2
    c = 3.00x10^8 m/s^2

    I = Fc/A

    I = 4.87x10^7 W/m^2

    This is my attempt at the solution. I think its correct but I would like to double check. I would appreciate any help. thank you
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Sep 19, 2008 #2

    LowlyPion

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    What's the area of that sheet of paper?
     
  4. Sep 19, 2008 #3
    A = 6.03x10^-2 m^2

    The area i had above was a typo
     
  5. Sep 19, 2008 #4

    LowlyPion

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    Homework Helper

    OK, no problem then.

    Except that maybe it will burn up?
     
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