Question

A beam of electrons passes undeflected through
mutually perpendicular electric and magnetic
fields. If the electric field is switched off, and the
same magnetic field is maintained, the electrons
move :-
(1) along a straight line (2) in an elliptical orbit
(3) in a circular orbit
(4) along a parabolic path​

Answer 1

Answer:

Correct Answer: B

Solution :

If both electric and magnetic fields are present and perpendicular to each other and the particle is moving perpendicular to both of  them with i1>i3>i2. In this situation 30−−√ and β. But if electric field becomes zero, then only force due to magnetic field axists. Under this force, the charge moves along a circle.

Answer 2

Explanation:

answer is first option