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Homework Help: Dimensions, Unit Operations Homework (True/False)

  1. Jan 19, 2009 #1
    1. The problem statement, all variables and given/known data

    X and Y are dimensionally different. (They have different units.) Select ALL the physically meaningful operations. State which are true or false
    1. X/Y or X*Y
    2. X+Y or X-Y
    3. e^(X/Y) or e^(X+Y)
    4. X^2 +Y^2 or X^X + Y^Y
    5. X^2 or Y^2
    6. X^(1/3) or Y^(1/3)

    2. Relevant equations

    3. The attempt at a solution

    I'm assuming

    1. True because you could have like velocity/second, etc.
    2. False, you can't add apples and oranges
    3. False no idea though
    4. False
    5. True
    6. True

    An explanation along with the correct answers would be greatly appreciated.
  2. jcsd
  3. Jan 19, 2009 #2


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    Homework Helper

    I believe you have all correct so far.

    For 3, I don't think it is possible to raise a constant to the power of a quanity.
    Else it'd be like saying 2^(4 kilograms) or e^(2 Newtons), it is physically meaningless.
  4. Jan 19, 2009 #3
    thanks a lot, if I could just have a complete confirmation since I only have one last try to get it right in the computer
  5. Jan 19, 2009 #4
    N/m i was right, thanks for the confirm tho
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