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## Homework Statement

A wire of total length 34.00 m, consists of equal lengths of Cu followed by Al, both having the same diameter of 0.80 mm. A voltage difference of 86.0 V is placed across the composite wire. What is the current flowing in the wire? Use rho=1.72x10-8 ohm-m for the resistivity of copper and rho=2.82x10-8 ohm-m for the resistivity of aluminum.

## Homework Equations

R

_{T}= R

_{Cu}+ R

_{Al}

R = rho*L/(pi*r

^{2})

R = V/I

## The Attempt at a Solution

Solve R = rho*L/(pi*r

^{2}) for both Cu and Al and add together for R

_{T}

(34*1.72*10^(-8))/(pi*.04^2) + (34*2.82*10^(-8))/(pi*.04^2)

= 0.000307089463

I = V/R

_{T}

86/0.000307089463

= 280048.684 ohm

Keep getting the wrong answer, what am I doing wrong?