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Author Topic: What would happen if everyone in China jumped at the same time?  (Read 18576 times)

Harry

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Harry asked the Naked Scientists:
   
Hello,

What would happen if all the people in China jumped up and down at the same time?

regards

Harry

What do you think?
« Last Edit: 26/04/2010 21:30:02 by _system »


 

Offline LeeE

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They would slightly compact the ground beneath them slightly, but other than that, not much.
 

Offline daveshorts

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They would move the earth slightly, on average. All the people in china weigh about 1 billion * 60kg -> 60 billion kg or 60 million tonnes.

The earth weighs 6 x 1024kg so about 1014 times more. This means that if they all jumped 1m in the air the earth would move about a 1014th of a metre, 19fm or 0.00000000000001m 

Far too small for anyone to notice, plus the earth isn't rigid and the force would take many minutes to travel across the earth.

If they were all in the same place, they might be able to make a small earthquake, if all the energy in their jump got transferred into the rock it would have a similar energy to an earthquake of 4-4.5 on the Richter scale.
 

Offline graham.d

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Shh! This is Britain's idea as a replacement for Trident.
 

Offline LeeE

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They would move the earth slightly

I think this would only happen if the Earth was perfectly hard and non-deformable.  It's not though, so I still think that you'd only get some local deformation.
 

Offline Geezer

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Even if the Earth did accelerate away from the "jumpers", it would return to its former position as they accelerated back towards the surface.
 

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