Question

When a charged particle moving with velocity $\overrightarrow{V}$ is subjected to a magnetic field of induction $\overrightarrow{B}$, the force on it is non-zero. This implies the

• A. Angle between $\overrightarrow{V}$ and $\overrightarrow{B}$ is necessary ${90}^o$
• B. Angle between $\overrightarrow{V}$ and $\overrightarrow{B}$ can have a value other than ${90}^o$
• C. Angle between $\overrightarrow{V}$ and $\overrightarrow{B}$ can have a value other than zero and ${180}^o$
• D. Angle between $\overrightarrow{V}$ and $\overrightarrow{B}$ is either zero or ${180}^o$

Answer 1

The correct option is C Angle between $\overrightarrow{V}$ and $\overrightarrow{B}$ can have a value other than zero and ${180}^o$

Force on a charged particle moving in a magnetic field is

$\overrightarrow{F}=q(\overrightarrow{v}\times \overrightarrow{B})$

Let the angle between $\overrightarrow{v}$ and $\overrightarrow{B}$ be $\theta$

Hence $\left|\overrightarrow{F}\right|=qvBsin\theta \ne 0$

$⟹sin\theta \ne 0$

$⟹\theta \ne 0^{\circ },{180}^{\circ }$