Graphene Aerogel - ...
 

[Closed] Graphene Aerogel - can someone explain how this works?

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I read this article last night and I can't get my head around it. How can something be 7 times lighter than air but is a solid?

http://www.extremetech.com/extreme/153063-graphene-aerogel-is-seven-times-lighter-than-air-can-balance-on-a-blade-of-grass

or is it a big hoax?


 
Posted : 09/10/2015 12:26 pm
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"lighter than air" - why doesn't it float then?


 
Posted : 09/10/2015 12:28 pm
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I don't know and thats why I can't fathom it out


 
Posted : 09/10/2015 12:30 pm
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[quote=cynic-al opined]"lighter than air" - why doesn't it float then?

Is it a witch?


 
Posted : 09/10/2015 12:36 pm
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[naive understanding]
The aerogel itself is less dense than air but is also air permeable which means that outside of a vacuum it will absorb air and therefore be heavier than air. I guess if it could be made and sealed without absorbing air then it would float (assuming the seal was also lighter...).

[/naive understanding]


 
Posted : 09/10/2015 12:40 pm
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I agree - that's how I read it too.


 
Posted : 09/10/2015 12:42 pm
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So much like a sponge is less dense than water and floats, until it's saturated, then it 'sinks'?


 
Posted : 09/10/2015 12:44 pm
 thv3
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"lighter than air" - why doesn't it float then?

Depends how many particles of "air" you're talking about. The air particles are also individual and so lighter than the Graphene Aerogel item as a whole.


 
Posted : 09/10/2015 12:45 pm
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Note, the original paper makes no claim about being lighter than air. The naive understanding above is a relatively good explanation.

Definitely not a hoax. Different types of aerogels have been around for a very long time (since 1931), they're just very expensive to produce.


 
Posted : 09/10/2015 12:45 pm
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The naive understanding above is a relatively good explanation.

Haha... That's some great damning with faint praise! ๐Ÿ™‚


 
Posted : 09/10/2015 12:48 pm