Earth rotation speed if it was tidal locked to the Sun

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Discussion Overview

The discussion revolves around the hypothetical scenario of Earth being tidally locked to the Sun. Participants explore calculations related to Earth's rotational speed at the equator under this condition, the nature of deceleration, and the mass required for an object to influence Earth's rotation significantly. The scope includes theoretical physics and speculative reasoning.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant confirms that Earth's current rotational speed at the equator is approximately 465.1 m/s.
  • Another participant suggests that if Earth were tidally locked to the Sun, its rotational speed could be calculated by dividing the circumference of the Earth by the length of a year, yielding a speed of about 4.57477 km/h.
  • There is a question about whether the deceleration from current speed to the tidally locked speed would be linear or exponential, depending on the gravitational influence of a passing object.
  • A participant raises the issue of what mass an object would need to be to significantly decelerate Earth if it passed at a distance similar to that of the Moon.
  • Some participants express uncertainty about the feasibility of such a scenario, questioning the conditions required for tidal locking and the implications of a massive object passing by Earth.

Areas of Agreement / Disagreement

Participants generally agree on the current rotational speed of Earth but have differing views on the implications of tidal locking, the nature of deceleration, and the conditions necessary for such a scenario. The discussion remains unresolved with multiple competing views and questions raised.

Contextual Notes

Limitations include assumptions about the nature of tidal locking, the effects of gravitational interactions, and the specific conditions under which these calculations would hold true. There are unresolved mathematical steps regarding the deceleration process and the mass of the influencing object.

Who May Find This Useful

This discussion may be of interest to those exploring theoretical physics, speculative scenarios in astrophysics, or creative writing involving scientific concepts.

MKP81
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Dear Forum,

I am filmmaker from Berlin and despite physics focus back in high school I am really bad at it. I am trying to get my head around some ideas I am working on and would kindly ask you for some tiny calculations. I hope this is OK and maybe even fun for someone here?

So my questions are:
The Earth spins at a speed of 465,1 m/s (A) at the equator, right?

How fast would the Earth spin at the equator if it would be tidal locked to the Sun (B)?

If the negative acceleration from A to B would take 20 years how many m/s slower the Earth would spin in a year?

Would the negative acceleration be linear or exponential if one passing object would "steal" the rotational energy through its own gravitational force. Like the moon does for example but much heavier of course.

What mass would such an object need to decelerate the Earth like this if it passes let's say about the distance of the moon?

I know it is nonsense. But fun to think about it!

I thank you so much.
 
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welcome to the forum
 
hsdrop said:
welcome to the forum
Thank you hsdrop!
 
are you writing a store based off the questions you asked??
there is a separate forum for that on the site for writers and stories that they are writing about
 
Yes I do. It it better to post/move there?
 
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in most creative writing storeys the writers forum is a bit more open to the "what if's" then the others just because the other deal in absolutes and lateral instead of the creative. throw i an looking up some of the answers to your questions now or at least the ones that i can explain some what easley
 
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for your first question
MKP81 said:
The Earth spins at a speed of 465,1 m/s (A) at the equator, right?
yes the Earth does spin at that speed hears a graph that shows a little more of how fast the Earth spins according to where you live on the planet
article-2546864-1B07A3AB00000578-149_634x365.jpg

for your 2 question
MKP81 said:
How fast would the Earth spin at the equator if it would be tidal locked to the Sun (B)?
well if the Earth was tidal locked to the sun that would mean that only one side of the Earth would face the sun at all times so if you take the circumference of the Earth and divide it by a year you would get your spin speed that comes out to about 4.57477...km/h

as for the other questions that you asked i would need a little help with answering them completely right
 
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what exactly are you asking for? Are you asking how fast would the equator move if a day took 365 days or how close would the Earth have to be in order to tidally lock in the first place? That can't happen where it is, it's way too far from the sun.
 
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