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Homework Help: Is this textbook example incorrect?

  1. May 23, 2013 #1
    1. The problem statement, all variables and given/known data

    Capture.jpg

    2. Relevant equations

    I got 4.5*10^22 /m^3 using the exact numbers that they used...

    which gives 4.5*10^16 /cm^3


    Is there some intermediate step which was not shown? ie. the numerical answer given by the equation is in some other unit which was converted to /m^3?
    3. The attempt at a solution
     
    Last edited: May 23, 2013
  2. jcsd
  3. May 23, 2013 #2
    wait, I think I made a mistake on my handheld calc

    I used this intead and got
    https://defuse.ca/big-number-calculator.htm
    (8*3.14*((2*9.11*10^31)^1.5)/(3*(6.625*10^-34)^3))*(1.6*10^-19)^1.5
    =4.5 325 569 071 841 6e+ 120
     
    Last edited: May 23, 2013
  4. May 23, 2013 #3
    nevermind, mr Donald neaman forgot a negative sign in front of the ^31...
     
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