Does resistivity depend on the thickness of the wire? I had a derrivation in my class about strain guages where we considered dp/dS - change in resistivity due to change in strain?
Yes, of course it does - the thicker the wire, the lower it's resistance (assuming the material is the same). Think of it like resistors in parallel, adding a second resistor in parallel will half the resistance - likewise doubling the cross sectional area of a wire will half it's resistance, just like using two wires.
Yes, of course it does - the thicker the wire, the lower it's resistance (assuming the material is the same). Think of it like resistors in parallel, adding a second resistor in parallel will half the resistance - likewise doubling the cross sectional area of a wire will half it's resistance, just like using two wires.
I dont think thats what he asked? The resistivity is the per unit area resistance of a given material. For example, the resistivity of copper is the same whether or not I make a wire of any thickness or a sheet of it.
However, if I add impurities to the copper, it's resistivity changes.
So, I think the answer to his question is NO. Resistivity (in a uniform material) is, by definition, independent of geometery such as a smaller diamter piece of wire.