Question

The diagram above shows atomic particles moving through a magnetic field.
A beam of electrons is deflected in the magnetic field and strikes at the point $P$ as shown in the figure.
At which letter would a stream of neutrons strike the screen?

• A. $A$
• B. $B$
• C. $C$
• D. $D$
• E. $E$

Answer 1

The correct option is B $B$

The force on a charge $q$ in a magnetic field $B$ moving with velocity $v$ is given by $F=qvB\sin \theta$ or $\overrightarrow{F}=q\overrightarrow{v}\times \overrightarrow{B}$ where $\theta$ is the angle between $\overrightarrow{v}$ and $\overrightarrow{B}$.

As neutron has no charge $q=0$, so it does not experience any magnetic force and will go straight to point B.