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Location, location, location.

  1. Jul 13, 2007 #1
    If I were at the equator and dropped a bowling ball in a bucket of water which is 45 degrees F, and dropped another ball of the same weight, mass, and size in a bucket of water at 30 degrees F, dropping them at the same time, which ball would hit the bottom of the bucket first? Same question, but the location is the north pole.
    Last edited: Jul 13, 2007
  2. jcsd
  3. Jul 13, 2007 #2


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    Oooh tricky.[The first one would beat the second one by 3-6 months]
  4. Jul 13, 2007 #3
    If the water were to provide even little resistance to motion, the second ball would reach the bottom of the bucket, since there is no water in the second bucket.[it's just a "bucket at 30 F", not a bucket of water.] It's the same case at the pole, too. And I have a feeling that I haven't understood the question really well. X-(
    Last edited: Jul 13, 2007
  5. Jul 13, 2007 #4


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    At 32 F water is frozen

    I think this question is unfair to all us metric people out here... can't you use SI units? :)
  6. Jul 13, 2007 #5
    Thanks for pointing that out, I edited the OP.
  7. Jul 13, 2007 #6
    Oh well, back to the drawing board.
  8. Jul 14, 2007 #7


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    I'd have to say the first one in both instances. The only way to be 30 degrees throughout the entire bucket is for the water to be frozen solid.

    I'm not sure a bucket is deep enough to give a good spread of temperatures, but if the top of a pond or lake is frozen, it's guaranteed that the bottom of the pond is 37 degrees - the temperature where water is most dense.
  9. Jul 14, 2007 #8
    Since a bowling ball floats in water ( search google video if you don't believe me ), and the frozen ice in the other bucket will not permit the ball to touch the bottom, I will say that NEITHER touches the bottom. This is for the case at the NORTH POLE The water will of course eventually freeze around the ball due to being at the north pole! But it should not touch the bottom.

    For the case at the equator, ball number 1 will win because the water in bucket 1 is already in liquid form and has a higher initial temp and thus will evaporate sooner than the water in bucket 2

    Both cases assume the ball was dropped from a fairly conservative height and that the balls weigh less than 11lb.(I read bowling balls over that weight sink). Many other things are assumed like your buckets are big enough to allow the ball to touch the bottom as well. :tongue:

    end of text
    Last edited: Jul 14, 2007
  10. Jul 14, 2007 #9
    That's interesting about the floating bowling balls. I had no idea. Let me stipulate that the balls are 16 lbs. each. I hadn't thought about the slow sinking of the ball into the ice. I don't think it would take months to reach the bottom though.
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