A 3.0mC charge moves northward at 250ms−1 through a region where a uniform 0.40T magnetic field points due east. What are the magnitude and direction of the magnetic force acting on the charge?
a) 0.30N, directed vertically upward
b) 0.12N, directed vertically downward
c) 0.30N, directed vertically downward
d) 0.30N, directed toward the west