Chances of Being Accepted for a Book Author as a Graduate Student
I don't know about physics, but in Computer Science book chapters tend to be the lowest class of peer-reviewed publication. Most book editors are struggling to get any good contributions, and the only chapter-books (as opposed to text books with a single, or few, dedicated authors) I really see succeed nowadays are written by a closed group of people for a specific purpose. For instance, I know that some Dagstuhl seminars collectively decide to write a book - every participant writes one or two chapters, often together with (a subset of) members of their research group.

For books with an open call, you can in my field basically never be too inexperienced to write a chapter, as long as your English is good. That said, I generally advise my students against writing one anyway. Chapters are fairly long, so they may take an inexperienced writer substantial time to write, and the reputation and scientific impact of having a chapter in a book that is virtually never read is so negligible that the same effort is better directed to writing a different kind of paper.

Finally, the reaction of your advisor may also be a hint that they don't value book chapters either. Even if you can get your chapter accepted, is it a good use of time to work on something that your advisor appears to not put much stock in?