American college duration................? ( BSc Physics )?

AP cles are not going to help him. Not all schools will take those for credit. If he has a degree already, he can try transferring some of the cles - depending on how many transfer, he could save himself a year or more of college. If he doesn't transfer any, it's going to take him about 4 years to complete a 4-year degree. Summer cles don't help much - you can't take too many at a time, they don't tend to offer advanced courses you need for the degree over the summer, and it keeps you from getting an internship in your field (which can be very important for physics majors, especially if he wants to go to grad school afterward).