1) Potential Difference An electron is accelerated through a potential difference of 2.2 kV and directed into a region between two parallel plates separated by 20 mm with a potential difference of 200 V between them. The electron is moving perpendicular to the electric field of the plates when it enters the region between the plates. What magnetic field is necessary perpendicular to both the electron path and the electric field so that the electron travels in a straight line?
2) Horizontal Conductor A horizontal conductor that is part of a power line carries a current of 7400 A from south to north. Earth's magnetic field (60.0 µT) is directed toward the north and is inclined downward at 70° to the horizontal. Find the magnitude and direction of the magnetic force on 150 m of the conductor due to Earth's field.