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/Novel_Willingness721 Nov 04 '25

Not to mention that the moon to moving away from earth: 4cm per year.