Thanks for the kind feedback. As far as I can tell, most science and engineering majors require comparable numbers of earned credit hours - close to 128 is common. This would be 16 credit hours per semester for 8 semesters for students starting with zero and planning for 4 years. But most students I mentor are able to keep their loads lower, because they tend to start with 20-40 earned credit hours from various high school programs - AP, dual enrollment, etc. Some are tempted to double major or try and graduate in fewer than 8 semesters, but I discourage that, encouraging instead for students to live life a bit more or focus on GPA or do more research, or both. So keeping loads from 12-15 credit hours is workable. Students starting with closer to 40 hours are also often able to include a minor which can better prepare them for graduate school, make them more appealing in campus research jobs, or better prepare them for employment. Most physics majors choose math or chemistry as a minor.
Students should also realize that the numbers in the original post are based on students with fairly strong high school backgrounds - ACT scores in the 30s. Students with ACT scores in the 20s (or comparable SAT scores) can certainly succeed in Physics and Chemistry majors if they work hard enough, but they will usually have to spend more time studying for a comparable level of accomplishment. Very few students with weaker high school backgrounds are willing to work this hard, so a lot more end up with GPAs in the 2.x range if they stay in Chemistry or Physics. They also tend to change their majors to Education or Biology or Computer Science.
