Write down the full Hamiltonian for a hydrogen atom in an external field. Next, calculate the energy changes deltaE (not absolute E) of the three orbitals Y01, Y11, and Y-11 induced by the applied magnetic field Bz. Interpret your results with respect to your knowledge of the time-evolution of the wavefunctions.
The Attempt at a Solution
In all honesty I have no idea how to start this. I know what a Hamiltonian operator is but that's about it. I understand that this forum isn't so that other people can do my homework for me, so can someone help me start in the right direction? Any help would be greatly appreciated.