I'm sure this is pretty basic, but I'm not very good at electricity.

At both ends of a conductor we apply 12 volts. For one minute an electric charge of 72 C passes through the conductor. What is the resistance of the conductor?

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    $\begingroup$ Hints: 1. Fill in the blank: resistance is a relationship between voltage and _________ ? (It's in your textbook, if you don't remember.) 2. How is the thing in the blank related to the quantities given in the problem (specifically the 72 C and the 1 minute)? $\endgroup$ – Ted Bunn Jul 14 '11 at 17:51
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    $\begingroup$ When 12 Volts are applied to one end, and 12 Volts are applied to the second end, there is no reason for a current. $\endgroup$ – Georg Jul 14 '11 at 17:56
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    $\begingroup$ I see Ted was kind enough to give you some hints, but as it says in our FAQ, you need to ask about the specific concept that's giving you trouble, not just give us your homework problem. If you can expand on why exactly you're having trouble with this and convert it into a more generally useful question, then I'll be happy to reopen it. $\endgroup$ – David Z Jul 14 '11 at 18:03

Current is the amount of charge passing though a surface area per second. If in 60 seconds 72C of charge flows through this surface, then in 1 second, 72C/60 flows, and that is your current I = 72/60 Amps.

Now use Ohms law, V = IR to find the resistance R with V = 12v and I = 72/60A

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