Do you need to be very good at introductory mechanics to do well in introductory E&M? Or can you still do good in E&M (get an A) if you are not very good at introductory mechanics? To prepare for intro E&M should I do (A) review intro mechanics or (B) start studying E&M from a book like serway or halliday/resnick. My goal is to get an A in intro E&M. Also do you have to be naturally good at physics (also error analysis) to major in it?