posted by Matt .
A high voltage power line carries a current of 110 A at a location where the Earth's magnetic fields has a magnitude of 5.9 x 10^-4 T and points north at an angle of72 degrees below the horizontal (toward the earth surface). Find the direction and magnitude of the magnetic force exerted on a 250m length of wire if the wire flows
a) horizontally toward the east
b) horizontally toward the south