1. The problem statement, all variables and given/known data An [itex]\alpha[/itex]-particle and a β-particle are both travelling along the same path at a speed of 1.5x106 ms-1. They then enter a region of uniform magnetic field. The field is a square with sides of 1 cm. The magnetic field is normal to the path of the particles and is into the plane of the paper. Calculate the ratio 'radius of the path of the alpha particle/radius of the path of the beta particle.' 2. The attempt at a solution I don't even know how to start thinking about this question. I mean I know that the radius of the alpha particle will be greater than that of the beta particle because of their differences in mass and charge but how do you do go about that in fractions?