Consider an aluminum wire of diameter 0.580 mm and length 28.0 m. The resistivity of aluminum at 20.0°C is 2.82 10-8 Ω · m.(a) Find the resistance of this wire at 20.0°C. ___________Ω(b) If a 9.00-V battery is connected across the ends of the wire, find the current in the wire. __________A
Aluminum has a resistivity of 2.65 x 10^-8. But I will use your figure of 2.82 x 10^-8. R = ρL/A where ρ = resistivity = 2.82 10-8 Ω · m, L = Length = 28 meters, A = Area =( .58mm/2)^2 x pi = 0.26 mm^2, or 2.6 x 10^-7 m^2 R= (2.82 x 10^-8)(28)/2.6 x 10^-7 = 3.03 ohms I=V/R = 9/3.03 = 2.97 amps
Resistivity Of Aluminum Wire
