An aluminium wire has a cross-sectional area 0140 x 10"5 m2 and carries a current of 5-0 A. If there are 1.8 x 102'3 free electrons per m3, calculate the mean drift velocity of the electrons. A copper wire of diameter 0-60 mm carries a current oi 2.0 A. The copper contains 8.0 x 10231ree electrons per m3. What is the drift velocity of the electrons? A gold wire contains 5.9 x 101"8 free electrons per m3 and has diameter 1.0 mm. If the electrons travel with a mean drift velocity of 0.50 mm s\