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Bubbles of Fun

  1. Apr 21, 2008 #1
    1. The problem statement, all variables and given/known data

    At 24.0 m below the surface of the sea (density = 1025 kg/m3), where the temperature is 5.00°C, a diver exhales an air bubble having a volume of 1.20 cm3. If the surface temperature of the sea is 20.0°C, what is the volume of the bubble just before it breaks the surface?

    2. Relevant equations

    P1V1/T1=P2V2/T2 (thats what i tried)

    3. The attempt at a solution
    i got answers like 4.8, 1.68 by plugging into the equation...but as usual plug and chug never works...can u help please? i think im missing how to find pressure from 24 m below surface. how do u do that?
  2. jcsd
  3. Apr 21, 2008 #2


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    Homework Helper

    It would be more helpful to a reader here if you showed the calculations you made, rather than simply giving the answers you found that didn't work. You do want to use the "Ideal Gas Law". Did you use absolute temperatures in your calculation (Kelvins, rather than degrees Celsius)? Did you remember that the pressure at 24 m. down is the hydrostatic pressure of 24 meters of water plus the one atmosphere of pressure from the air above the water's surface?

    Have you had the topic on hydrostatic pressure? The pressure from the water will be

    P = (density of water) x (g) x (depth of water).
    Last edited: Apr 21, 2008
  4. Apr 21, 2008 #3
    no we havent covered that so wat pressure wud i used for when its just about to break the surface of the water since i dont know exactly how deep it is? wud that just be 1 atm?
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