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When a charged particle moving with velocity $\vec{V}$ is subjected to a magnetic field of induction $\vec{B}$, the force on it is non-zero. This implies that :-
A
Angle between $\vec{V}$ and $\vec{B}$ is necessarily $90^\circ$
B
Angle between $\vec{V}$ and $\vec{B}$ can have any value other than $90^\circ$
C
Angle between $\vec{V}$ and $\vec{B}$ can have any value other than zero and $180^\circ$
D
Angle between $\vec{V}$ and $\vec{B}$ is either zero or $180^\circ$
Detailed Solution
Magnetic force on a moving charge: $\vec{F} = q(\vec{V} \times \vec{B})$
Its magnitude is $F = qVB\sin\theta$, where $\theta$ is the angle between $\vec{V}$ and $\vec{B}$.
When $\theta = 0^\circ$ or $\theta = 180^\circ$, $\sin\theta = 0$ and therefore $F = 0$.
For every other value of $\theta$, $\sin\theta \neq 0$ and the force is non-zero.
The force is maximum at $\theta = 90^\circ$, but it is not necessary that the angle be $90^\circ$ for the force to be non-zero.
So a non-zero force implies that the angle between $\vec{V}$ and $\vec{B}$ can have any value other than zero and $180^\circ$.
Its magnitude is $F = qVB\sin\theta$, where $\theta$ is the angle between $\vec{V}$ and $\vec{B}$.
When $\theta = 0^\circ$ or $\theta = 180^\circ$, $\sin\theta = 0$ and therefore $F = 0$.
For every other value of $\theta$, $\sin\theta \neq 0$ and the force is non-zero.
The force is maximum at $\theta = 90^\circ$, but it is not necessary that the angle be $90^\circ$ for the force to be non-zero.
So a non-zero force implies that the angle between $\vec{V}$ and $\vec{B}$ can have any value other than zero and $180^\circ$.