Calculate the resistance of a 1km length, 1mm diameter wire made from: a) constantan (\rho = 4.9 × 10-7 Ωm)
b) copper (\rho = 1.7 × 10-8 Ωm)

c) State which material is better suited for being used to make resistors, and justify your answer.
d) With 1 amp of current flowing through each of the wires how much energy is converted to heat?
e) What potential difference would be needed to force a current of 1 amp through that length of each type of wire?