Can anyone help with this problem, I have tried it a number of ways and can not get the correct answer, thanks in advance. Two isotopes of carbon, carbon-12 and carbon-13, have masses of 19.93 10-27 kg and 21.59 10-27 kg, respectively. These two isotopes are singly ionized (+e) and each is given a speed of 7.00 105 m/s. The ions then enter the bending region of a mass spectrometer where the magnetic field is 0.6600 T. Determine the spatial separation between the two isotopes after they have traveled through a half-circle. I have been using the equation r=mv/eB but I think that I may be inputting the incorrect value for e since all the other variables are given.