What length of an alloy wire of resistivity 5.0x10^-7 Ωm and diameter 0.50mm is required to make a standard 6.0Ω resistor?
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hillo (
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October 10th, 2009
What length of an alloy wire of resistivity 5.0×10^-7 Ωm and diameter 0.50mm is required to make a standard 6.0Ω resistor?
Please could you show your workings so I can see how you worked it out plus the answer so I can make sure I’m doing it right
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15 Answers
Interesting homework question.
I’m not knowledgeable about physics, but putting myself in the shoes of someone who is.. Why don’t you post the answer that you got, and show your work, and ask us where you went wrong on the problem.
For a cylindrical resistor, the general formula for its value of resistance is R = [(resistivity)*(length)]/(area), where area is the cross sectional area of the resistor.
For your problem, you know R and resistivity, and the cross sectional area can be calculated easily (area = pi*r^2). The only unknown variable is length. I’ll leave the simple arithmetic up to you.
@Ivan
I feel silly now :P I must be tired, I some how skipped over 6.0Ω and couldn’t make the formula.
@hillo I feel below you because I haven’t the slightest clue to what this gibberish is, or maybe the lack of will to learn.
@Samurai
No need to feel “below” anyone, you’d pick it up really quickly if you were being taught the material. Basically, when you try to run an electric current through a wire, the wire “resists” the flow of current. The amount it resists depends on what it’s made out of, how long it is, and how thick it is.
@Ivan Then putting everything in algebraic expressions, I guess it would be easy to learn with the know how.
@Samurai
There is no need to feel below me. As Ivan has just said “you’d pick it up really quickly if you were being taught the material.”
If you’ve never been taught it or bothered to learn it how would anyone expect you to know?
Maths isn’t someone I find natural, plus I’m a idiot don’t let this fool you. :)
@Ivan . . .your mom didn’t resist my cylinder. . .
@hillo
@Ivan
I meant that as a form of speech as to mean ununderstanding of what you understand in the current moment.
@Ivan . . .that’s what i told your mom.
The link was nice. I’ve never been so aroused by electricity.
@Blondesjon
This is what we spend our time doing at MSU.
@Ivan . . .So you do have a sense of humor. Color me impressed.
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