Question: (A) What value of magnetic field would make beam of electrons , travelling to the right at a speed of 4.7× 10^7 m/s , go undetected through a region where there is a uniform electric field of 8500V/m pointing vertically up?
(B) What is the direction of magnetic field if it is known to be perpendicular to the electric field ?
(C) What is the frequency of the circular orbit of the electric field is turned off?