1. this year I finished off my course of Physics I (the first general physics) at my university and we had a lot of exercises to do where in order to complete them I had to change the system coordinates, for example, from Cartesian to polar coordinates. But the book that I was using didn't have any theory explaining how to change coordinates and I had to use my intuition to solve it. Anyway, can you recommend any material (books, videos, etc) about coordinate changes in basic physics?

  2. Also, is there any other books for basic physics that you guys recommend? I was using Halliday but it's so superficial and Morin was so complicated, I couldn't find any intermediary level book.

Ps: I'm asking for this content because even though I had good grades in the subject I don't think I've learned some stuff properly.