I'm not looking for books which deal with the mathematical foundations of Newtonian mechanics. What I'm looking for are modern books which deal with conceptual foundations of Newtonian mechanics - by that I mean exact definition of force, inertia, frames of reference etc. It seems like much of the books that deal topics were written before the 80's or even older (like the one by Ernst Mach himself). And the people who seem to be bothered about these things today are mostly science educators, who again publish very little on these topics. I'm not looking for books written from a philosophical standpoint either. Something that'd be comprehensible by a undergrad would be just fine.
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