Residential building codes typically require the use of 12-gauge copper wire (diameter 0.205 cm) for wiring receptacles. Such circuits carry currents as large as 20.0 A. If a wire of smaller diameter (with a higher gauge number) carried that much current, the wire could rise to a high temperature and cause a fire. (Table of resistivities)
(a) Calculate the rate at which internal energy is produced in 1.95 m of 12-gauge copper wire carrying a current of 20.0 A.
(b) Repeat the calculation for a 12-gauge aluminum wire.
Explain whether a 12-gauge aluminum wire would be as safe as a copper wire.