Question

When a charged particle moves at right angles to a magnetic field then which of the following quantities changes

• A. energy
• B. momentum
• C. speed
• D. all of the above

Answer 1

The correct option is A energy

REF.Image

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

Due to this force the particle moves in a circular path.

Thus, the direction of motion changes i.e, $\overrightarrow{V}$ (velocity) changes.

$\Rightarrow$ Momentum changes because $\overrightarrow{P}=m\overrightarrow{V}$