Question

A 14-gauge copper wire has a diameter of 1.628 mm. What magnitude current flows when the drift velocity is 1.00 mm/s?

Answer 1

The electric current

$$I=jA=envA\\ =1.6*10^{-19}*8.50*10^{28}*1.00*10^{-3}\\ *3.14*(1.628*10^{-3})^2/4=28.3\:\rm A$$