The diameters of copper wires A and B are equal. The current carried by wire A is twice the current carried by wire B. In which wire do the charge carriers have the higher drift speed?
I= qnAv relates the current I in a wire to the charge q of the charge carriers, the number density n of charge carriers, the cross-sectional area A of the wire, and the drift velocity v of the charge carriers.
Since wire A carries the larger current, then its drift speed must be larger since the quantities are directly proportional.