# Could the earth stop spinning one day??

Discussion in 'Astronomy, Exobiology, & Cosmology' started by Vega, Jul 14, 2006.

1. ### Janus58Valued Senior Member

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Take a paper clip, first straighten it out a little and then bend it back and forth a few times, feel the point at which you bent it, it will feel warm.
The human sense of "warmth" does not kick in until 82°F (something will have to be at least this temp before you will register a sensation of warmth.) assuming that paper clip started at room temp ~70°F, its temp has raised ~13°F or ~7°C

3. ### superluminalI am MalcomRValued Senior Member

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You're wrong MK. It's not an analogy. It's a scaling. If you had some engineering training you'd know that scaling problems, keeping the relevant quantities equivalent (in this case angular momentum) is a well known way of attacking a problem. It's completely valid. There are no more or fewer "options" for analysis at either scale. I've already provided the math at the scale of the earth and you don't seem to be getting it. The lead ball demonstration puts the magnitude of the problem in a bit more human-scale perspective.

5. ### superluminalI am MalcomRValued Senior Member

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Exactly! This is the exact reason I gave the scaled example of the spinning 2m lead ball. It puts the magnitude of what he's proposing into a more understandable form.

7. ### MetaKronRegistered Senior Member

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We simply do not heat up any mass to any significant degree by accelerating it at 0.04 gees, pushing it or in freefall. The same thing does not happen at 1000 gees.

8. ### superluminalI am MalcomRValued Senior Member

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What does the deceleration have to do with anything? No one is complaining about the deceleration. The heating would come from the flexing of the planet due to tidal stress, just like Jupiter's moon Io, which is the most geologically active world in the solar system because of it. Only the earth would never get to experience any heating as it would be torn apart well before that by differential tidal stress.

Can we forget about the heating and focus on the immense torque that this would take? I mean, the impossible torque?

9. ### MetaKronRegistered Senior Member

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And you were the one who was talking about scaling the problem?

10. ### superluminalI am MalcomRValued Senior Member

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Huh?

I have no idea what you're talking about. Plus your responses are getting shorter with each post. Are we wearing you out with facts and actual physics?

11. ### Janus58Valued Senior Member

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You keep wanting to focus on the wrong issue. It has nothing to do with the resultant acceleration and everything to dop with hiow efficient the mechanism causing that acceleration is.

If I accelerate a hunk of Iron with an magnetic field, the magnetic field will generate eddy currents(circular electric currents) in the iron. Those eddy currents will heat the Iron. A percentage of the field's energy will go into heating the metal rather than accelerating it.

Tidal forces are very inefficient when it comes transfering angular momentum between two bodies. A large percentage of the energy involved comes out as heat.

12. ### MetaKronRegistered Senior Member

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You are definitely not managing to do that.

13. ### Walter L. WagnerCosmic Truth SeekerValued Senior Member

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resurrecting this old thread based on recent information showing it might be correct, as here: http://www.theguardian.com/science/2014/jan/06/gassy-planet-same-mass-earth-discovered-scientists