1. The problem statement, all variables and given/known data Consider a helium ion with 2 neutrons and 2 protons in the nucleus and 1 bound electron. Use the Bohr model with corrections for charge and mass of the nucleus. Calculate the energy in the ground state. 2. Relevant equations m*v*r = n*(h/2*pi) 3. The attempt at a solution Basically I'm confused how to make the corrections to the Bohr model for charge and mass. I'm fine with the rest of the question, I've just never seen an example of making the correction. Thanks.