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View Full Version : Determination of the resitivity of a wire


bacumba
Feb 16, 2009, 09:40 AM
Pics available to demonstrate the experimnent

rwinterton
Feb 16, 2009, 09:54 AM
The usual experiment is to pass an accurately known current through a wire of uniform cross section. Use a four-point probe (two junctions -- current goes through two of the wires, the other two wires go to a very high-impedance, very high precision voltmeter_ to measure the drop in voltage across the wire. You then measure the length of the wire between the two junctions and calculate the resistivity (resistance per unit length).

Remember Ohm's law.