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**1. Homework Statement**

In the circuit shown, two thick copper wires connect a 1.5 V battery to a Nichrome wire. Each copper wire has radius R = 7 mm and is L = 18 cm long. Copper has 8.4 × 10^28 mobile electrons per cubic meter and an electron mobility of 4.4×10^−3 (m/s)/(V/m). The Nichrome wire is l = 5 cm long and has radius r = 3 mm. Nichrome has 9 × 10^28 mobile electrons/m3 and an electron mobility of 7 × 10^−5 (m/s)/(V/m). What is the magnitude of the electric field in the copper wire? Answer in units of N/C

**2. Homework Equations**

[itex]\bar{v}[/itex][itex]_{thin}[/itex]=(A[itex]_{thick}[/itex]/A[itex]_{thin}[/itex])[itex]\bar{v}[/itex][itex]_{thick}[/itex]

[itex]\bar{v}[/itex] = uE

E=V/L

**3. The Attempt at a Solution**

I plug in my known values, but I have two unknowns, the electric fields. I'm not sure how to use these equations.