Apoint charge of 5.7 µc moves at 4.5 × 105 m/s in a magnetic field that has a field strength of 3.2 mt, as shown in the diagram. what is the magnitude of the magnetic force acting on the charge? a) 6.6 × 10–3 n b) 4.9 × 10–3 n c) 4.9 × 103 n d) 6.6 × 103 n