(a) Using the data in Table 18.1, compute the resistance of a copper wire 3 mm (0.12 in.) in diameter and 2 m (78.7 in.) long.
(b) What would be the current flow if the potential drop across the ends of the wire is 0.05 V?
(c) What is the current density?
(d) What is the magnitude of the electric field across the ends of the wire?