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

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A

Straight line

B

circle

C

helix

D

Cycloid

Solution:

the force due to electric field=qE Force due to magnetic field=qvBsin $\theta=0$
i.e. magnetic field does not exert any force .but the particle experience a force due to electric field and gains velocity. So the particle will move in the direction of the electric field along a straight line

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