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Dadgum it, it turned out to be easier than I expected to come up withThe situation presented seems a dilemma if you require that W = Int F dot
a problem that doesn't lend itself to Q+W=delta(E). Gene Mosca
provided me with it.
Drop a block. The earth does work on the block. But the block does no
work on the earth (because the earth's motion is negligible). Oops!
The resolution of this situation is of course to include the energy
of the gravitational field. But unless one is willing to talk about
work done on a field (and I don't think I am), there's no way to
include this term on the LHS of the 1st law as stated above.
The only way out, I must concede, is to admit that Q+W=delta(E) is
not useful anytime field forces (which are external to the system)
are involved. Unfortunately this includes large numbers of problems.