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Homework Help: Metric conversion

  1. Feb 11, 2010 #1
    1. The problem statement, all variables and given/known data

    kf2tc8.jpg

    I have no idea how they got this answer. It says "doing the division gives you..." What division? It doesn't tell me what has been divided. The centimeters into grams? I can't find any plausible division that would give me .002 for an answer. I've been staring at this for an hour.
     
  2. jcsd
  3. Feb 11, 2010 #2

    jhae2.718

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    It's basic dimensional analysis. The unit conversion factors used are:
    1 kg = 1000 g
    1 m= 100 cm thus 1 m3 = 1 x 106 cm3

    Multiply/divide the original expression by these factors so that the kg and m units cancel out and you'll get the answer shown.
     
  4. Feb 12, 2010 #3
    Thanks for the reply.
    I keep coming up with .02 as an answer, not .002. I must be setting up the multiplication/division equation wrong.
    I multiply the 1000g times 20kg to get 20,000g and divide it by 10^6 centimeters?
     
  5. Feb 12, 2010 #4

    jhae2.718

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  6. Feb 12, 2010 #5

    collinsmark

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    I think you are doing it correctly. Problem with book's answer.
     
  7. Feb 12, 2010 #6

    Redbelly98

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