Question

Ionized hydrogen atoms and $\alpha$-particles with same momenta enters perpendicular to a constant magnetic field. B. The ratio of their radii of their paths $r_H : r_\alpha$ will be :

• A. 4 : 1
• B. 1 : 4
• C. 2 : 1
• D. 1 : 2

Answer 1

Answer: (C)

2 : 1

Answer 2

$r_{H} = \frac{p}{eB}$
$r_{\alpha} = \frac{p}{2eB}$
$\frac{r_{H}}{r_{\alpha} } = \frac{\frac{p}{eB}}{\frac{p}{2eB}}$
$\frac{r_{H}}{r_{\alpha}} = \frac{2}{1}$