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Mass/Density problem - please check my working.

  1. Sep 10, 2012 #1
    1. An olympic pool is 50m long 25m wide and a minimum average depth of 2m
    a) If the pool is filled as specified, what is the mass of water? Denisty of water to be 1.0g/cm^3
    b) How long will it take to fill the pool from a standard garden hose, if the flow rate from hose has average of 8 liters per minute?

    2. Relevant equations (density = mass/volume)(volume = LxWxH)

    3. a) Volume = 25 x 50 x 2 = 2500m^3
    Convert density to kg/m^3, 1g/cm^3 = 1000kg/m^3
    mass = 2500 x 1000 = 2.5e5kg

    b) I just did m^3 into liters, so 2500m^3 = 2.5e5liters
    =312500min approx 217 days

    I know its basic question, with unit conversation etc, but I have no answers to check my working. Thanks
    Last edited: Sep 10, 2012
  2. jcsd
  3. Sep 10, 2012 #2


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    Welcome to PF bentleyq!

    Check your arithmetic. 2500 * 1000 = 2.5e6. You're too low by a factor of 10.

    Your conversion to litres is also similarly wrong.
  4. Sep 10, 2012 #3
    Ah thanks, i should be 2.5e6liters also, but seems i still have the correct time of 312500min???
  5. Sep 10, 2012 #4


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    Looks okay to me! EDIT: your answer for the time, I mean.
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