A particle having a mass of 10-2 kg carries a charge of 5 x 10-8 C. The particle is given an initial horizontal velocity of 105 ms-1 in the presence of electric field and
magnetic field.
To keep the particle moving in a horizontal direction. it is necessary that
1) 
should be perpendicular to the direction of velocity and 
should be along the direction of velocity
2) Both 
and 
should be along the direction of velocity.
3) Both 
and 
are mutually perpendicular and perpendicular to the direction of velocity
4) 
should be along the direction of velocity and 
should be perpendicular to the direction of velocity.
-
(1) and (3)
-
(3) and (4)
-
(2) and (3)
-
(2) and (4)
C.
(2) and (3)
Both 
and 
should be along the direction of velocity and Both 
and 
are mutually perpendicular and perpendicular to the direction of velocity.
