An alpha particle (α), which is the same as a helium-4 nucleus, is momentarily at rest in a region of space occupied by an electric field. the particle then begins to move. find the speed of the alpha particle after it has moved through a potential difference of −3.45×10⁻³ v . the charge and the mass of an alpha particle are α = 3.20×10⁻¹⁹ c and mα = 6.68×10⁻²⁷ kg , respectively.