Comparing radii and time periods of two particles in a magnetic field.

An element can have multiple forms, these forms are called isotopes. Using magnetic field, we can separate the different isotopes from a sample of the element.

Isotopes ${\text{X}}_1$‍ and ${\text{X}}_2$‍ of an element have masses $m_1$‍ and $m_2$‍ respectively. They are given charge $q$‍ and $-q$‍ respectively and released in a magnetic field with speed $v$‍ as shown.