Question

A charged particle is released from rest in a region of steady uniform electric and magnetic fields which are parallel to each other. The particle will move in a

• A. Straight line
• B. Circle
• C. Helix
• D. Cycloid

Answer 1

The correct option is A

Straight line

Since the charged particle is at rest, initially, the magnetic field will not make it move, but initially the charged particle will experience an electrostatic force in the direction of electric field as a result of which it gains a velocity parallel to E or parallel to B and hence even after the motion of the particle it will not experience a magnetic force i.e. its trajectory is a straight line