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Automatic-Leave-7258 t1_itu9hov wrote

That’s… not how energy works at all.

Moving 1 gram 1 meter can cost energy if you move the 1 gram to a higher potential, be energy neutral if the two endpoints are at the same potential, or even generate energy if you move the 1 gram to a lower potential.

The method you use to get it there can be more or less efficient, and it is almost always energy negative in practice due to friction… but what matters isn’t the mass being moved, it’s the integral of the force applied with respect to the distance traveled. That’s the definition of “work.”

The cool thing is that by this definition, you spend energy to accelerate a mass in the beginning, but as you slow the mass down to approach its destination, you can recover almost all of that energy as you apply a negative force to decelerate.

In fact, this is what the alternator in your car does. As you brake, the alternator recaptures energy used to accelerate the wheels, and it stores that energy in the battery.

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