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## 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 = 0.009m and is L = 0.17m long. Copper has [itex]8.4 \times 10^{28}[/itex] mobile electrons/[itex]m^3[/itex] and an electron mobility of [itex]4.4 \times 10^{-3}[/itex](m/s)/(V/m). The Nichrome wire is L2=0.08m long and has radius R2 = 0.003m. Nichrome has [itex]9.0 \times 10^{28}[/itex] mobile electrons/[itex]m^3[/itex] and an electron mobility of [itex]7.0 \times 10^{-5}[/itex] (m/s)/(V/m).

a). What is the magnitude of the electric field in the thick copper wire?

b). What is the magnitude of the electric field in the thin Nichrome wire?

## Homework Equations

I = nAuE

v = uE

## The Attempt at a Solution

First I just tried to analyze the copper wire section.

L = 0.17m

R = 0.009m

n = [itex]8.4 \times 10^{28}[/itex]

u = [itex]4.4 \times 10^{-3}[/itex]

A = [itex]2.54 \times 10^{-4}[/itex]

I began to plug this into I = nAuE to solve for E until I realized that I don't know I. So I tried substituting v/u into the equation so that I = nAu(v/u) = nAv, but then I realized that I don't know what the drift velocity (v) is..