few general formulas

[nix85]

again you are not getting it, just because book
ended in the same location does not mean work
has not been done. you used energy to do work
both ways, work has been done. that it's pointless
or useless work is totally irrelevant

[lancaIV]

subjective or objective view-point :


https://translate.google.com/translate?sl=auto&tl=en&u=https://de.wikipedia.org/wiki/Arbeit_%28Physik%29


If the direction of the force is not parallel to the direction of the displacement path, only the force component that is parallel to the path is effective.


If the force is perpendicular to the direction of movement, it does no work (an example would be wind pressure acting on a moving train from the side).


If the force is anti-parallel to the displacement path, the work done is negative, as in the first example.


If the direction of the force is perpendicular to the path, no physical work is done.


The physical term does not correspond to the everyday understanding according to which every porter is paid for the work they do.

[nix85]

again you are not getting it, just because book
ended in the same location does not mean work
has not been done. you used energy to do work
both ways, work has been done. that it's pointless
or useless work is totally irrelevant

[lancaIV]

You are right,when the positive Joule ,probably vectorical less negative Joule, in the total scalar sum calculation is greater 0,zero !






Sincere


OCWL

[nix85]

sum is not zero since work has been done
overall energy in the universe is 0 but that is another thing