Ebb and flow

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Kevin_Hall
Asternaut
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Ebb and flow

Post by Kevin_Hall » Thu Jan 06, 2022 6:56 pm

I may have lost my mind, but I have no clue about how the ebb and flow work. Well, I understand that Moon attracts water, which is more elastic than the earth. Hump A on the top of Earth is formed. But how does hump B on the opposite side form?

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Chris Peterson
Abominable Snowman
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Re: Ebb and flow

Post by Chris Peterson » Thu Jan 06, 2022 7:06 pm

Kevin_Hall wrote: Thu Jan 06, 2022 6:56 pm I may have lost my mind, but I have no clue about how the ebb and flow work. Well, I understand that Moon attracts water, which is more elastic than the earth. Hump A on the top of Earth is formed. But how does hump B on the opposite side form?
The Moon does not "attract water" any differently than it attracts rock. The water is more deformable, so it forms a kind of oblate sphereoid (which it would do it there was only water, and no earth at all). The solid(ish), much less deformed body of the planet is centered in this deformed water body.
Chris

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neufer
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Re: Ebb and flow

Post by neufer » Thu Jan 06, 2022 8:03 pm

Kevin_Hall wrote: Thu Jan 06, 2022 6:56 pm
I may have lost my mind, but I have no clue about how the ebb and flow work. Well, I understand that Moon attracts water, which is more elastic than the earth. Hump A on the top of Earth is formed. But how does hump B on the opposite side form?
  • "Hump A" is pulled up by the nearness of the sublunar Moon.

    "Hump B" is pushed away by centrifugal force of Earth swinging around the Moon.
Both forces are maximum when the Moon is at zenith: "on the top of Earth";
however, the delayed F=ma affect causes both "Humps" to occur at a later time in Earth's rotation.
Art Neuendorffer