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?
anyone know what kind of graph to expect if i am plotting
a.) diameter - resistance
b.) area - resistance
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- Thread Starter
- 13-03-2004 19:44
- 13-03-2004 20:04
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.
- 13-03-2004 23:02
You may wish to use the relationship that the resistance of a uniform wire is:
R = (resistivity * length)/cross-sectional area