A cyclotron is used for the acceleration of alpha particles. The radius of the cyclotron?s dee is 2 m, and the magnetic flux density in the dees is 0.8 T. What is the velocity of the alpha particles when they exit the cyclotron? The alpha particle consists of two protons and two neutrons, thus having mass of 6.64 x 10-27 kg and charge of 2x1.6X10-19C.