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How much space does a Pound of copper use

  1. Mar 5, 2012 #1
    I am trying to figure out if you have one pound of copper density 8.95 and if you have a pound of silver density 10.4 how much space each will take or how much more space the copper will take this can be ounce's or whatever metric measurement they use for volume
    as I put a pound of copper in water then took out the copper and put a pound of silver in the water and I came up with about three to four nickels (5 cents) worth of volume difference and I was going to figure out if this is about the right amount of volume? Will 8.95 divided by 10.4
    which is .86 be an indicator as if you had a cubic foot of copper that with silver it would only be .86th of a cubic foot of silver or does it not work that way?

    John
     
  2. jcsd
  3. Mar 5, 2012 #2

    mathman

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    You have the right idea.
     
  4. Mar 5, 2012 #3

    cmb

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    Best not to work in pounds, but refer to kilogrammes.

    A pound of copper is heavier than a pound of silver.

    Confusing, huh!?

    A pound of silver = 373.24 g
    A pound of copper = 453.59 g
     
  5. Mar 5, 2012 #4
    I kinda worked it out starting with the weight of a pound of copper and silver in one cubic foot then taking 7.48 gallons in a cubic foot times 128 ounces in gallon and I come up with 1 pound of silver taking up 1.47 ounces of space and for copper taking up 1.74 ounces of space, if you could physically pour copper and silver I hope this is right.

    John
     
  6. Mar 6, 2012 #5

    mathman

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    Where did you get this idea? Are you assuming Troy weight for silver and Avoirdupois for copper?
     
  7. Mar 7, 2012 #6
    I am trying to figure how much the thickness of 1 pound of silver would be in 3.5" diameter the formula goes as follows:

    diameter 3.50"
    radius 1.75"
    X
    radius 1.75"
    X
    pie 3.14
    =
    sq. Inches 9.6162

    cubic inches
    in sq. foot 1728

    divided by 9.66162
    =
    179.6938 < cylinder 3.5" diameter should be this many inches long

    Pound of silver
    per cu. foot 660

    divided by 179.6938
    =
    per inch 3.6729 pounds

    divided by 4
    =
    per quarter in. .918225 pounds

    Here is my problem as I know that 3.5 inch diameter 1/4 inch weighs .918225 pounds
    how much thickness in decimal format is needed to make 1 pound?

    John
     
  8. Mar 7, 2012 #7

    cmb

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    Of course. What other measurement system would you use for silver with 'pounds' in it, other than Troy?
     
  9. Mar 7, 2012 #8

    mathman

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    I suspect that the original question assumed the same unit of weight for both copper and silver.
     
  10. Mar 7, 2012 #9
    The OP seems to revolve around Archimede's principle; a fine idea.
    Most of the replies show how the imperial/american system of units revolve around lots of awful conversion factors; a terrible fact.
    (Please, consider this reply as a tongue in cheek comment)
     
  11. Mar 7, 2012 #10
    I seem to finally figured it out as 1 pound of silver would need a space of 3.5" dia. X .272" lg.
    1 pound of copper would need a greater space as density is less. I always use inches as I do not no the metric system that well and the result is always the same anyway.

    John
     
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