An alpha particle is a helium nucleus with 2 protons and two neutrons and a mass of 6.64 E-27 kg. A particular alpha particle is traveling horizontally with a velocity of 40 m/s when it encounters a uniform vertical magnetic field of 1.10 T. What is the diameter of the path of the?-particle? What effect does the B field have on the speed of the particle? What are the magnitude and direction of the acceleration vector while the particle is in the field?