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Movie Dark Waters 2003

  1. Jan 19, 2013 #1
    Hey folks i have a doubt of this old movie, 3 of the main characters are on submarine and the submarine lost power so one of the mans pick the Inflatable Boats and by the hatch throw below of the submarine and then the submarine inflated to the surface. I mean really fake right this scene??? thanks for future answers.
    Last edited: Jan 19, 2013
  2. jcsd
  3. Jan 21, 2013 #2


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    It's a little hard to read what you wrote. An object will float to the surface as long as its density is less than the density of water. And that density is "mass divided by volume". Now, if I read this correctly, they take an inflatable boat, push it outside a hatch (without letting water in?) and inflate it. Since the boat and air (compressed) were already on the submarine, so there is no change in mass in doing that. However, the volume is now the original volume of the submarine plus the volume of the inflated boat. If the submarine was already close to neutral bouyancy, that added volume might well push the density below that of water.
  4. Jan 21, 2013 #3
    But note that if they are at a decent depth, the air put into the boat to inflate it would expand on it's way up and the boat would explode without a method of releasing the excess volume of air.
  5. Jan 25, 2013 #4
    thanks for answer now i see sci fiction ^^ anyway thanks for the answer the inflate boat is tiny then the submarine so doesn't make sense anyway but the trend is to go up right not to sink?
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