The force on a charge moving with velocity v in a magnetic field B is half of the maximum force when the angle between v and B is
-
A.
90o -
B.
45o -
C.
30o -
D.
0o
Correct Answer: Option C
Explanation
the force on a moving charge in a magnetic field is given by: F = q V β sin θ
and this force is maximum when θ = 90o, during which sin 90o = 1: and for sinθ = 0.5, θ = 30o