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Surface Areas of Spheres

  1. Dec 10, 2011 #1
    1. The problem statement, all variables and given/known data

    The question wants me to use this formula: ((4pi)^(1/3))((3v)^(2/3))

    You have filled two round water balloons with water. One balloon contains twice as much water as the other balloon.

    Compare the surface areas of the two water balloons using the given formula.

    2. Relevant equations


    3. The attempt at a solution

    I don't know where to start
    And I Don't Know where they got the answer from.

    The book gave me a final answer as: The balloon with twice as much water will have about 1.59 times the surface area of the balloon with less water.
  2. jcsd
  3. Dec 10, 2011 #2


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    Homework Helper

    Say the volume of the other balloon is x. The volume of the first balloon is twice the volume of the other balloon, so that's 2x. Plug in x into the formula above and simplify. Then do the same for 2x. Compare the two expressions.
  4. Dec 10, 2011 #3
    ok, will try and let you know
  5. Dec 10, 2011 #4
    Yes, it worked, I got about 1.59, thank you
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