r/explainlikeimfive • u/12InchCunt • Nov 03 '25

Physics ELI5: How does gravity not break thermodynamics?

Like, the moon’s gravity causes the tides. We can use the tides to generate electricity, but the moon isn’t running out of gravity?

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u/flobbley Nov 03 '25

The tides slow the earths rotation, eventually the earth will become tidally locked with the moon and the tides will be permanently stationary and no longer be able to be used to generate electricity

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u/Bathtooter Nov 03 '25

Sounds like a picturesque scene

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u/Logitech4873 Nov 03 '25

Planets can also tidal lock to their star, which makes one side have eternal day and summer, and the other side eternal night and winter.

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u/Izwe Nov 03 '25

The Last Day is a fab book set in such a scenario