Earth Slowing Down: What Would People Feel?

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Discussion Overview

The discussion explores the hypothetical scenario of the Earth slowing down to a halt over a period of five years, focusing on the physical sensations and forces that people might experience as a result. It encompasses theoretical calculations, implications for weather patterns, and the effects of such a change on daily life.

Discussion Character

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

Main Points Raised

  • Some participants suggest calculating the linear velocity of a person at the equator to understand the forces involved in the Earth's deceleration.
  • One participant calculates that the required deceleration to stop the Earth's rotation in five years would be approximately 0.0000003g, which they argue would likely be unnoticeable to people.
  • Another participant points out that the rotational speed at the poles is significantly lower than at the equator, leading to different experiences of deceleration.
  • Some participants express curiosity about the fate of the Earth's angular momentum and its implications for weather patterns, particularly the Coriolis effect on hurricanes.
  • A participant draws an analogy to aircraft landings, suggesting that a gradual deceleration over five years would fundamentally alter the experience of landing.

Areas of Agreement / Disagreement

Participants express varying views on the noticeable effects of deceleration, with some arguing it would be imperceptible while others highlight significant climatic changes. The discussion remains unresolved regarding the overall impact on human experience and environmental consequences.

Contextual Notes

Participants rely on various assumptions about the Earth's rotational dynamics and the effects of deceleration, which may not be fully explored or agreed upon. The calculations presented depend on specific definitions of velocity and acceleration.

Who May Find This Useful

This discussion may interest those exploring theoretical physics, environmental science, and the implications of rotational dynamics on weather and human experience.

guysensei1
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I was watching a documentary that examines what happens if the Earth slowed to a halt in the span of 5 years.

One point they didn't cover was that since the Earth is slowing down at a greatly accelerated pace, what would the people feel? How much apparent force would they feel acting on them?
 
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Why won't you try and calculate the linear velocity due to Earth's rotation of a person standing on the equator(it's the highest there). It's as easy as dividing the equatorial circumference by the length of day in seconds.
With that in hand, calculate the acceleration required to slow down to 0 m/s over five years( ##ΔV=aΔt## ). Compare the acceleration to e.g. the gravitational acceleration.

Tell us what you think about the result.
 
The Earth rotates at one circumference per day, which is roughly 500m/s at the surface. If it takes 5 years to slow down to zero, then it must decelerate at 100m/s/year, which is about 0.000003m/s^2, or roughly 0.0000003g. That's not very much, and I suggest, given all the climatic change and geophysical/tidal effects i suspect might happen, would probably not be noticeable. Great episode though...
 
a_potato said:
The Earth rotates at one circumference per day, which is roughly 500m/s at the surface. If it takes 5 years to slow down to zero, then it must decelerate at 100m/s/year, which is about 0.000003m/s^2, or roughly 0.0000003g. That's not very much, and I suggest, given all the climatic change and geophysical/tidal effects i suspect might happen, would probably not be noticeable. Great episode though...
It's not 500m/s at the poles.If you stood at one of the poles a short distance away,you would rotate around it at approx 1 metre a day.
So if you walked from the equator to the pole it would give you a pretty good idea of what you would feel if the Earth slowed down to allmost a halt.
 
Buckleymanor said:
It's not 500m/s at the poles.If you stood at one of the poles a short distance away,you would rotate around it at approx 1 metre a day.
So if you walked from the equator to the pole it would give you a pretty good idea of what you would feel if the Earth slowed down to allmost a halt.

Thats true. 500m/s is at the equator, which is the fastest linear velocity at the surface of the earth, and would therefore exhibit greatest linear deceleration should the Earth's rotation change. At the poles, you wouldn't notice any change, apart from the massive climatic apocalypse happening around you. I do wonder where all those exajoules of rotational energy end up though - presumably into moving whatever unseen body is slowing the earth...
 
Just imagine yourself on a recent aircraft trip. Instead of taking a few minutes to land or take off, imagine it takes five years.
 
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One has to wonder, where is all that angular momentum going? (It's conserved.)
Ignoring the impossibility of it, it would have a huge effect on weather. Hurricanes spin CCW in the northern hemisphere and CW in the southern hemisphere because of the coriolis force. Without rotation, there's no coriolis force, so hurricanes would be greatly transformed.
 

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