A college physics professor was explaining a somewhat complicated concept to his class, when a pre-medical student
interrupted him and the following conversation started:
Pre Medical Student: Why do we have to learn this?
Professor: To save lives.
Professor continued his lecture again, but soon he was interupted by the same student again:
Pre Medical Student (Questioned laughingly): So how does physics save lives?
Professor: Physics saves lives because it keeps idiots out of medical school.