Question

1. The free electron density of the aluminum used in high voltage transmission lines is n = 2.08 × 10^(29) m^(-3) . The resistivity of that aluminum is ρ = 2.66 × 10^(-8) Ωm. A particular line of this high transmission line is carrying 1.4GW (1.4 × 10^(9) W) of power at a voltage of 550kV (5.5 × 10^(5) V ) over a distance of 200km. The electrons in this wire are travelling at a drift velocity of vd = 0.2mm/s. How efficient is this wire? Follow the steps below to find out.

1a) What is the current through this wire?

1b) Given your answer in part a, what is the cross sectional area of this wire?

1c) Given your answer in part b, What is the resistance of this wire?

1d) Given your previous answers, how much power is lost during transmission?

Answer 1