Magnetic vs Electric Force Direction · CAP 2007 #17
Physics · electromagnetism
Problem
One reason why we know that magnetic fields are not the same as electric fields is because the force they exert on a charge +q, is:
(a) in opposite directions in electric and magnetic fields if the charge is moving;
(b) parallel to the magnetic field and perpendicular to the electric field if the charge is moving;
(c) parallel to the electric field and perpendicular to the magnetic field if the charge is moving;
(d) zero in the electric field and nonzero in the magnetic field if the charge is not moving;