A copper wire has a diameter dCu = 0.0435 cm, is L = 4.69 mlong, and has a density of charge carriers of 8.50E28electrons/m^3. As shown in the figure, the copper wire is attachedto an equal length of aluminum wire with a diameter dAl = 0.0111 cmand density of charge carriers of 6.02E28. A current of 0.400 Aflows through the copper wire.
a) What is the ratio of the current densities in the two wires,JCu/JAl?
b) What is the ratio of the drift velocities in the two wires,vd-Cu/vd-Al?
