Question

A charged particle moves in a uniform magnetic field of induction $\overrightarrow{B}$ with a velocity $\overrightarrow{v}$. The change in kinetic energy in the magnetic field is zero when the velocity $\overrightarrow{v}$ is

• A. Parallel to $\overrightarrow{B}$
• B. Perpendicular to $\overrightarrow{B}$
• C. At any angle to $\overrightarrow{B}$
• D. At a fixed angle to $\overrightarrow{B}$

Answer 1

The correct option is C At any angle to $\overrightarrow{B}$

As the charge is travelling with constant speed, the kinetic energy will not change for any angle to $\overrightarrow{B}$ .