Magnetic and Electric Fields from Current-Carrying Wires · PhysicsBowl 2015 #29
Physics · electromagnetism
Problem
An electron moves at constant non-zero velocity directly between two long straight wires. The conventional current in each wire has the same magnitude, but the currents are in opposite directions as shown in the figure. Ignoring gravity, which choice best reflects the direction of the magnetic field and the direction of the electric field that exist at the location of the electron? Any electric field in the region originates from an unseen external source. [Figure: Two parallel wires with currents in opposite directions, electron moving between them]| Electric Field | Magnetic Field | |
|---|---|---|
| (A) | No field | No field |
| (B) | To the left | Into the plane of the page |
| (C) | To the right | Into the plane of the page |
| (D) | To the left | Out of the plane of the page |
| (E) | To the right | Out of the plane of the page |