Asingly charged ion of mass m is accelerated from rest by a potential difference δv. it is then deflected by a uniform magnetic field (perpendicular to the ion's velocity) into a semicircle of radius r. now a triply charged ion of mass m' is accelerated through the same potential difference and deflected by the same magnetic field into a semicircle of radius r' = 4r. what is the ratio of the masses of the ions?