these toy problems, universally deployed
"on the x-axis, because we can set-up the coordinates
in any way we like," always omit acceleration,
which is a bit of a problem in getting beyond "gedanken"
to any actual physical test ... of which plenty
have been made, of course.

anyway, why is it so hard to see that
the internal (angular) momenta of atoms has
to be considered, in accelerating them --
that these sub-atomic entities are also limited
by the speed (not velocity) of lightwaves
(not 0d rocks o'light, as in Newton's untheory,
where corpuscles go faster in a denser medium) ??

why do we need an aether,
when all of the major properties of interstellat plasma
have been worked-out in the lab
by the school of Alfven?

http://21stcenturysciencetech.com/edit.html