I just took a first semester of a first year physics course for scientists and engineers. Even though I thought that course work was rather rigorous, I did well and got an A in the course. I'm thinking about going into biophysics, but need to have a GPA in the range of 4.0-3.9 since I plan to attend medical school. I was wondering how much harder are upper division physics courses like electrodynamics, quantum mechanics, mathematical physics, computational physics, etc. than freshman physics and whether it is realistic to achieve a 4.0 in them while working 10 hours a week and doing research?