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I may regret jumping into this debate at this point, and on a small point
When an auto engine drives the tires, the work done by the engine is
somehow instantly conducted along the drive shaft. Yet all I see is a
turning shaft. By looking only at the spinning shaft, I cannot tell if
the engine is sending "work" to the tires, or the opposite: if the engine
is turned off and the car is coasting and is sending "work" from the tires
to the engine. In both cases the shaft just spins.
Ah, but what if I SUDDENLY turn the crank? Or what if the engine SUDDENLY
starts up with a jerk? Then (if I have fast eyes) I will see one end of
the shaft twist a bit while the rest stays still. A wave of "twisting"
will race down the shaft and the far end will finally begin turning. So,
the shaft doesn't simply turn, there also is a wave of "something" that
moves from one end to the other. The stuff that moves is wavelike, but I
can only see it when the speed of the engine suddenly changes.