JEE Advanced · 2021 · 03 Oct 2021 · Paper 1 · Magnetic Effects of Current

An $\alpha$-particle (mass 4 amu) and a singly charged sulfur ion (mass 32 amu) are initially at rest. They are accelerated through a potential V and then allowed to pass into a region of uniform magnetic field which is normal to the velocities of the particles. Within this region, the $\alpha$-particle and the sulfur ion move in circular orbits of radii ${\mathrm{r}}_{\alpha }$ and ${\mathrm{r}}_{\mathrm{s}}$, respectively. The ratio $\left({\mathrm{r}}_{\mathrm{s}}/{\mathrm{r}}_{\alpha }\right)$ is ____.