Reactive Current - Parallel RCL

[nix85]

You push the book across the table and then push it back to the starting place.

Indeed, net work on the book is NOT zero.

You done work in form of friction in both directions.

This friction scraped away millions of atoms on the bottom of the book and top of the table during the relative motion.

Even without friction work is done by your muscles to accelerate/decelerate the book 2 times. ATP is broken down into ADP + Pi (adinosine diphosphate + inorganic phosphate) and energy is released.

In any case work is done.

Keep looking in that mirror while chewing on your veggie until you understand work has been done.

[lancaIV]

nix85, actio/reactio ( ".... in both directions  ...) and the "Paradoxon"- explication in demonstrative manner !

I fix a magnet to a kitchen fridge door ! When ends the external/internal work process,
by classical physics formulation,by quantum physics formulation ?

Only the magnet/fridge in mind,the surrounding ambient ?

Oh,pardon-me,it is now time for " Essen fassen/almocar" !
Mahlzeit or Bon Appetit or Apgrand

[nix85]

Don't try to muddy the waters now. Read what you wrote

"If you move the book at constant speed horizontally,you don't do any work on it, despite the fact that you have to exert an upward force to counter-act gravity."

and realize how wrong it is. In your example work is done in many ways, first chemical conversion and contraction of your muscles, acceleration/deceleration of the book, friction against the table, air resistance (small but there).

[lancaIV]

Probably we will also discuss " primary energy work" and " secondary energy work" point of view !? But based by the " Pushing force does the work" quantitative and qualitative example !
Included Paradoxon their contradictions !
Later !

[nix85]

You will write any kind of nonsense rather that admit you were wrong, why am i not surprized.