Class 12 NEET Physics Moving Charges and Magnetism

Force acting on a charged particle moving with velocity

→

v

is subjected to magnetic field

→

B

is given by

→

F

=q(

→

v

×

→

B

);F=qvB‌sin‌θ
(i) When θ=0°,F=qvB‌sin‌0°=0
(ii) When θ=90°,F=qvB‌sin‌90°=qvB
(iii) When θ=180°,F=qvB‌sin‌180°=0
This implies force acting on a charged particle is non-zero, when angle between

→

v

and

→

B

can have any value other than zero and 180°.