A beam of electrons is accelerated through a potential difference of 1.0 kV before entering a velocity selector. If the magnetic field of the velocity selector has a magnitude of 0.010 T, what magnitude of the electric field is required if the electrons are not to be deflected as they pass through the velocity selector

A beam of electrons is accelerated through a potential difference of 1.0 kV before entering a velocity selector. If the magnetic field of the velocity selector has a magnitude of 0.010 T, what magnitude of the electric field is required if the electrons are not to be deflected as they pass through the velocity selector