Why doesn't tidal force pull earth and moon together?

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Discussion Overview

The discussion centers on the nature of tidal forces and why they create tidal bulges on Earth rather than pulling the Earth and Moon together. Participants explore the physics behind tidal forces, referencing various sources and critiques of existing explanations.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant questions why tidal forces stretch the Earth and create two tidal bulges instead of pulling the Earth and Moon together, likening it to pulling on a rubber band.
  • Another participant expresses skepticism about common explanations provided by oceanographers, asserting that they often misinterpret the physics involved and incorrectly invoke centrifugal force.
  • A participant references a document that they believe provides a better explanation of tidal forces, emphasizing the role of a non-uniform gravitational field.
  • There is mention of a specific chapter in a text by Hicks that discusses differential tidal forces, which some participants find well-defined and comprehensive.
  • Concerns are raised about inconsistencies in explanations found in different chapters of the same text, questioning the clarity of the initial explanations provided.

Areas of Agreement / Disagreement

Participants express differing views on the explanations of tidal forces, with some agreeing on the inadequacies of common oceanographic explanations while others defend certain texts. The discussion remains unresolved regarding the best interpretation of tidal forces.

Contextual Notes

Participants highlight limitations in existing explanations and the potential for confusion stemming from the use of terms like "centrifugal force." There is also a noted dependence on specific definitions and interpretations of tidal forces.

AlonsoMcLaren
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Why does tidal force strectechs the Earth and creates two tidal bulges, like pulling on a rubber band, instead of pulling Earth and moon together?
 
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Check out
http://tidesandcurrents.noaa.gov/publications/Understanding_Tides_by_Steacy_finalFINAL11_30.pdf"
 
Last edited by a moderator:
Gannet said:
Check out
http://tidesandcurrents.noaa.gov/publications/Understanding_Tides_by_Steacy_finalFINAL11_30.pdf"
*Sigh*

Oceanographers use the wrong explanation. Almost inevitably. It is a bad, bad meme in the oceanography world. While oceanographers do do oceanography well, that doesn't extend to physics. You don't need centrifugal force to explain the tides, centrifugal force does not explain the tides, and what they are calling centrifugal force is not the centrifugal force! The tide generating forces are the result of a non-uniform gravitational field. Period.

A few oceanographers do get it right. This article, http://oceanworld.tamu.edu/resources/ocng_textbook/chapter17/chapter17_04.htm, is a bit better than most. As much as people like to malign wikipedia, their suite of articles on the tides are pretty dang good.
 
Last edited by a moderator:
D H said:
*Sigh*...

Hicks does get into differential tidal forces in Chapter 5, which I think is very well explicitly defined and takes into account both lunar and solar tidal generating forces. That's why I lead the OP to this document.
 
Gannet said:
Hicks does get into differential tidal forces in Chapter 5, which I think is very well explicitly defined and takes into account both lunar and solar tidal generating forces. That's why I lead the OP to this document.
Ahh. So Hicks does. So why that nonsense in chapter 1?
 

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