Question

A current of I=8.0A is flowing in a typical extension cord of length L=3.00m. The cord is made of copper wire with diameter d=1.5mm.

The charge of the electron is e=1.6×10⁻¹⁹C. The mass of the electron is m=9.1×10⁻³¹kg. The resisitivity of copper is ρ=1.7×10⁻⁸Ω⋅m. The concentration of free electrons in copper is n=8.5×1028m⁻³.

A. Find the drift velocity vd of the electrons in the wire.

B. The population of the Earth is roughly eight billion people. If all free electrons contained in this extension cord are evenly split among the humans, how many free electrons (N_e) would each person get?

Answer 1