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Weight problem, need help

  1. Oct 2, 2006 #1
    Here's the question:

    It is determined by immersing a crown in water that its volume is 26in^3 = 0.015ft^3.

    What would its weight be if it were made of pure gold?
    What would its weight be if it half of its volume were gold and half lead?

    I'm not sure how to solve. I know this for gold:

    D = 19,300kg/m^3
    Dw = 1200lb/ft^3

    I thougt the two equations needed would be the following:

    m = V X D (since we know volume)
    followed by....
    W = mg, where m is solved for above and g = 9.8.... My answer of 2837 didn't make much sense....
  2. jcsd
  3. Oct 2, 2006 #2
    Well figure out what you do know, e.g. what is the weight of the crown out of water if gold? What would the combo weight be? What is the weight of an equivilant amount of water?

    Dw is the density of gold?.?

    The density of lead is 709 lb/cubic foot, and the density of water is 62.4 lb/cubic foot in case you didn't know.
    Last edited: Oct 2, 2006
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