Question

what happens to cathode rays when they are subjected to an strong electric field

Answer 1

Answer:

Cathode rays are stream of electrons. Electrons are negatively charged and they get attracted to positive potentials. Thus, as seen in the diagram below, if the electric field is perpendicular to the direction of cathode ray, then the ray will deflect towards the electric field (positive side).

Answer 2

Answer:

When the cathode rays are passed through an electric field between two parallel plates, cathode rays are deflected towards positive plate. This determines the charge of the particles constituting the cathode rays. As these are deflected towards positive plates, the particles of cathode rays are negatively charged.