Question about the Earth and Constant Angular Momentum

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Discussion Overview

The discussion centers around the concept of constant angular momentum in relation to the Earth's rotation and axial tilt. Participants explore the implications of these concepts and their interconnections, as well as the possibility of replicating constant angular momentum in other contexts.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that the Earth's tilt of 23.5 degrees contributes to its constant angular momentum and queries whether this tilt is essential for maintaining rotation.
  • Another participant questions the relevance of the tilt in relation to constant angular momentum.
  • A participant argues that the concepts of rotation and angular momentum are equivalent, emphasizing that the absence of external forces maintains constant momentum.
  • Some participants clarify that angular momentum is related to the axis of rotation, suggesting that the tilt and angular momentum are not directly connected.
  • One participant proposes a theory regarding the Moon's formation and its influence on Earth's axial tilt, asserting that the tilt is crucial for maintaining the balance of angular momentum in relation to the Moon's orbit.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between the Earth's tilt and its angular momentum, with no consensus reached on whether the tilt is essential for maintaining constant angular momentum.

Contextual Notes

Some statements rely on assumptions about the nature of angular momentum and its relationship to axial tilt, which remain unresolved within the discussion.

FeDeX_LaTeX
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The Earth is rotating because of constant angular momentum, right?

Would I be correct in interpreting that this is because the Earth's tilt is at an angle of 23.5 degrees, and so this angle is what causes it to keep spinning?

Is it possible to replicate constant angular momentum? And, to put it into comparison, would a good way of putting it be to think about a swing in a park that swings 360 degrees around the bar, then continues to swing 360 degrees forever?

If constant angular momentum holds true for the Earth, does that mean that the Earth will ALWAYS orbit at its velocity?

Thanks

EDIT: I just read that the axial tilt of Mercury is 0 degrees (no tilt). So how does the constant angular momentum work?
 
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Why do you think that the tilt makes a difference?
 
because it says constant *angular* momentum... am I interpreting it wrong?
 
FeDeX_LaTeX said:
The Earth is rotating because of constant angular momentum, right?

Well, the fact that the Earth is rotating and the fact that the Earth has angular momentum are two ways of saying the same thing.

For comparison: if an object has a velocity, and no force acts upon it, then the velocity will remain the same. This can equivalently be phrased as follows: when no force acts upon an object the linear momentum is constant.

Being equivalent statements either one implies the other; that is the relation between the two.

There's no connection with the concept of causal relation; it makes no sense to say something like 'the constant angular momentum causes the velocity to remain the same.'
 
FeDeX_LaTeX said:
because it says constant *angular* momentum... am I interpreting it wrong?
Angular momentum is around the axis of rotation. The tilt is of the axis of rotation. They are unrelated.
 
Yes the tilt is apart of the angular momentum, and I will explain why. There is a theory that the moon came from Earth because of a massive collision around the birth of our earth. The collision created our moon and also over time the Earth's axis was manipulated by the orbit of the moon or in the initial collision. In order to keeps its angular momentum the axis is tilted to keep the balance between the two being orbit vector of the moon and the rotation of the earth. If the tilt wasn’t present the orbit vector of the moon being on an angle, would not maintain an equal orbit to the hill sphere. So the angle of Earth is crucial for the orbit vector to maintain its trajectory with a moon with an orbit such as the one Earth has.
 

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