An atom is moving east inside a vacuum chamber that is close to the Earth's surface. As it moves, the atom experiences air drag with a magnitude of 2.243 x 10^-16 N. The vacuum chamber contains a uniform electric field and a uniform magnetic field, so the atom will not change trajectory or speed. The electric field has a magnitude of 1400.0 N/C and cancels out the air drag. The magnetic field in the chamber has a magnitude of 1.220 x 10^-9 T. The atom also has a kinetic energy K = 10^-18 J. Earth's magnetic field does not have an effect here.
a. What direction does the magnetic field point in compass directions or up/down?
b. What is the mass of the atom? Solve algebraically first by finding an expression for the charge of the atom. No velocity value given, only that the atom has constant speed and trajectory.