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Homework Help: Resistance again

  1. Feb 21, 2004 #1
    Not an actual problem, but I'm not sure how to figure these out.

    I am given the mass of a sample of aluminum. (Let's say it's 112g or something) I am given a shape: cylindrical tube, with the conditions that the diameter of the circular face = the height. (Also given, density of aluminum, a chart with the resistivity values, at standard temp of 20C). How on earth would I find the resistance between the top and the bottom face of the shape?
  2. jcsd
  3. Feb 22, 2004 #2
    R = pl/A (Resistance = resistivity * length/area) is probably the equation to use. But I have no length? The mass given, and density can find the length somehow? (I would use area of a circle only correct?)
    Last edited: Feb 22, 2004
  4. Feb 23, 2004 #3


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    Is the shape a "cylindrical tube" or just a cylinder?

    Since you haven't given a tube wall thickness I'm assuming you mean a cylinder.

    But you said,
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