Q:

Looking for a textbook on electromagnetism

I am looking for a free physics textbook on electromagnetism that wouldn't throw at me things to remember rather I'd love to have something which builds notions block by block, deriving coulomb's law instead of just presenting it as is for example.

A:

The Classical Theory of Fields
by L.D. Landau & E.M. Lifshitz
https://archive.org/details/TheClassicalTheoryOfFields/page/n65
this is worth studying in detail.

