How to read and understand successfully a physics book in any branch of physics ?
That is a very general question. I think there are a lot of complementary answers, but in general I would always recommend allocating plenty of time for doing many exercises. (Or, if these are not present, doing lots of "gap filling" in the main text.) The exercises are at least as important as the theoretical development.
I'll go a step further and say that this is a very VAGUE question. If you only have high-school level physics knowledge, you have no ability to read and understand Jackson's Classical Electromagnetism book, no matter how hard you try. This is because you are not equipped with the necessary tools and background information to understand the material. Think of a toddler who had only played with tinker toys, wanting to build a skyscraper.
If you have the necessary background and skill, then I'll quote a part of Mary Boas's "To The Student" preface from her book "Mathematical Methods in the Physical Science", which definitely applies to the study of physics. So replace "mathematics" with "physics" in this text, and the advice is perfectly valid as well:
In other words, you can't just "read" a physics text the way you read a novel. It is not a passive exercise. You have to work through a particular topic or chapter and you need to be able to solve a number of problems on that topic. This is the only way to be able to understand what you read in physics.
Thank you very much krylov and Zapper Z for your answers. I just wanna tell you that I finished my first three years as undergraduate student, now I'm about to start my first msc year in condensed matter physics, but I'm not satisfied with my study method. So I understand from what you have said to me that I must do plenty of exercises than relying on reading. But excuse me I have another question which is : How to fill my gaps in my study field especially gaps that I didn't discover yet ?
I was wondering why you are not satisfied with your study method? Also, what gaps in your knowledge do you typically encounter? I can imagine that for a prospective theorist these gaps may be mathematical, but for an experimentalist they may relate to electronics.
In general, I would say that as soon as you encounter a gap in your knowledge, and you think it is a gap worthwhile filling, take a book and do additional active reading. However, one can also go overboard with this: While still studying physics, I found many gaps in my knowledge of mathematics that required fixing, and I ended up getting a degree in mathematics instead.
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