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resistance and ohms law?

hi i have done an experiment about how the diameter (and therefore area) of a 60 cm piece of nichrome wire affects it's resistance. i used 5 different diameters - 0.315,0.376,0.457,0.559 and 0.712 mm.

I have got my results, but in the prediction i know that that if the diameter of a wire is increased, the cross sectional area of wire is also increased. This will cause the resistance to decrease, because the electrons have more room in which to flow. I also believe that the larger the area of wire, the lower the resistance.

but i really need to link this back to ohms law, and am finding this bit tricky. please can someone help?

thankyou

anyone know what kind of graph to expect if i am plotting

a.) diameter - resistance
b.) area - resistance
Reply 1
surely it's not hard to prove that if larger diameter gives a lower resistance then larger area gives lower resistance.

Since the area is the diameter squared times pi, it will be a curve.
Reply 2
You may wish to use the relationship that the resistance of a uniform wire is:

R = (resistivity * length)/cross-sectional area

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