Q. An electron enters a region where magnetic field ($\overrightarrow{B}$) and electric field $\left( \overrightarrow{E} \right)$ are mutually perpendicular to one another then
A) It will always move in the direction of $\overrightarrow{B}$
B) It will always move in the direction of $\overrightarrow{E}$
C) It always possesses circular motion
D) It can go undeflected also
Explanation
(d) If force on the electron due to electric field is equal and opposite to the force on electron due to magnetic field, then electron will go undeflected.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.