I am getting addicted to working on physics problems. I really want to keep my momentum with this going because I haven't had this much of an academic drive in a while. Right now I am studying electrodynamics. Where can I find lots of good problems in physics? I try to find some online but they are usually too easy. I dont want to do these surface level problems you find on YouTube. Is there anywhere I can get mastering physics style problems? I have Griffiths 2nd edition and I can't find the solutions to the problems to check if I'm right.