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Negative exponent in denominator

  1. Jan 30, 2010 #1
    So, I took an exam on conversion of units in chemistry and I put a negative exponent on the bottom:

    100s* 1nanoseconds/10^-9s = 10^11 ns,

    Is this wrong? If it's possible in math, why not in chemistry? My professor marked all my answers wrong due to this. Is there any way to argue my reasoning? Thanks in advance.
  2. jcsd
  3. Jan 30, 2010 #2

    Char. Limit

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    It is correct, although it would be better to write it with 10^9 ns in the numerator and 1 s in the denominator.

    But it is right, and your chemistry teacher was wrong to mark it wrong.
  4. Jan 30, 2010 #3
    What can I do? She will not give me the points back...
  5. Jan 30, 2010 #4


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    I don't think there's much you can do, unfortunately. Take note, and do things the way she wants on future assignments and tests.
  6. Jan 30, 2010 #5


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    I think it is very clever. What was her argument about it being wrong? Maybe you can get a physics teacher on your side.
  7. Feb 2, 2010 #6


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    What you've shown here is perfectly correct. Is it possible that you made mistakes in other parts of the problem that gave you the wrong final answer?

    If you attach a scanned page from your marked test, we can tell you exactly where any mistake is (or if there is none).
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