A copper wire and an iron wire of equal length l and diameter d are joined, and a potential difference V is applied between the ends of the composite wire. Calculate the potential difference (in volts) across the iron wire. Assume that l = 2.00 m., d = 0.30 mm., and V = 156 V.
The Attempt at a Solution
156 * 10 / (10+1.7) = 133.33 volts
156 * 1.7 / (10+1.7) = 22.67 volts
My question is: where do these equations come from? What are the derivations?
Thanks in advance.