1)The typical wire we might use could be made of Aluminum (resistivity 2.75 x 10^-8 ohm m. The length of the wire is 2.00m. Calculate the diameter we would need to have a resistance of 4.00 x 10^-3 ohm. How does this diameter compare with typical diameters used for copper wires? This may give you a hint as to why we can neglect the resistance of wires for circuits that have resistances in the range of one ohm and up. Do a similar calculation for wires made of tungsten ( resistivity = 5.25 x 10^-8 ohm m and copper (resistivity 1.69 x 10^-8 ohm m).
2)Write a brief essay on why resistivity is an important property to measure for solid materials. Include a discussion of what the temperature dependence of resistivity is at low temperatures (near absolute zero). Historically, the examination of resistance at low temperature led to the discovery of superconductors!
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