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Homework Help: From a Chemistry Textbook

  1. Apr 27, 2009 #1
    "one of the aims of the SI system of units is to remove unnecessary units. Since volume is length x breadth x height, i.e length3(small 3, don't know how to type it though), there is no need for the litre and the SI unit of volume is the metre cubed (m3) which equal 1000 L"

    I'm sure i'm missing something here...

    What if I had the following specifications: length = 2km, Breadth =1m, Height = 2m.

    This would not bring about the same result as 2000 x 2000 x 2000 which is presumably what length3 is.

    I wish I had paid much more attention in math class... any help with this.

    This is not homework, I'm currently studying Chemistry in my own time. I'm not enrolled anywhere so have no-one to ask for help. I jumped ahead a few chapters when I first started, but now I finding I need to know the math...
  2. jcsd
  3. Apr 27, 2009 #2


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    I'm not entirely sure what you're asking here, but I think you're essentially asking this:

    Is 1000 m^3 the same as 1000x1000x1000 m?

    The answer to that is, no it's not. 1000 m^3 is a thousand cubic meters, which if you'd put into a cube would have a side of 10m (the cubic root of 1000 is 10: 10x10x10=1000)

    1000m x 1000m x 1000m is a thousand meters, cubed, which is a billion cubic-meters.
  4. Apr 28, 2009 #3
    Wait until you study energy (Newton-meters) and torque (meter-Newtons).
  5. Apr 29, 2009 #4
    I don't mean to nit-pick but Newton-meters is work, not energy.
  6. May 3, 2009 #5
    i dont mean to nit pick but I would say newton metRE.. :smile:
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