Question

A charged particle is moving with velocity $v$ in a magnetic field of induction $B$. The force on the particle will be maximum when

• A. $v$ and $B$ are in the same direction
• B. $v$ and $B$ are in Opposite direction
• C. $v$ and $B$ are perpendicular
• D. $v$ and $B$ are at an angle of ${45}^o$

Answer 1

Answer: (C)

$v$ and $B$ are perpendicular

Force $=q(\overrightarrow{V}\times \overrightarrow{B})$
$=qVB\sin 0$
Where, $0$ is angle between velocity and magnetic field.
So, $\sin 0$ is maximum when $0$ is ${90}^o$ or velocity is perpendicular to magnetic field.