Two Singly Ionized Isotopes, X and Y, of the Same

Multiple Choice

Two singly ionized isotopes, X and Y, of the same element move with the same speed perpendicular to a uniform magnetic field. Isotope X follows a path of radius 3.35 cm while isotope Y moves along a path 3.43 cm in radius. What is the ratio of the two isotope masses, m_Y/m_X?

A) 0.977
B) 0.954
C) 1.05
D) 1.02