A rectangular loop of copper wire is placed on a horizontal table. In three different time intervals, electrons within three labeled segments of the loop drift as described below. The cross-sectional area and electron number density are the same in all segments.
• Segment A: electrons drift northward with speed vA
• Segment B: electrons drift eastward with speed 2vA
• Segment C: electrons drift southward with speed 21vA
Assume the magnitude of the electron charge is e and the drift speeds are steady in each segment.
(a) For each segment (A, B, C), state the direction of the conventional current. Express each direction using compass terms (north, south, east, or west).
(b) Rank the magnitudes of the conventional currents in the three segments from largest to smallest. If any currents have equal magnitude, indicate that explicitly.
(c) Justify your ranking in part (b) by referencing the relationship among charge, drift velocity, and current, and by explaining why the sign of the charge carriers matters.