1. The problem statement, all variables and given/known data An alpha particle: He++ captures an electron of a given kinetic energy. To conserve energy, it emits light, hf. How would one calculate the frequency? 2. Relevant equations E=hf En = (Z^2 *-13.6eV)/(n^2) 3. The attempt at a solution Calculate En. Then KE = Photon + En. Solve for v given KE and En?