posted by jewel on .
copper has 8.5 x 10^28 electrons per cubic meter. (a) how many electrons are there in 30 cm length a 12 gauge copper wire (diameter 2.05 mm)? (b) if a current of 1.55 A is flowing in the wire, what is the average drift speed of the electrons along the wire? (There are 6.24 x 10^18 electrons in 1 coulomb of charge.)