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This page (revision-18) was last changed on 04-Jan-2013 13:33 by pgaillard  

This page was created on 23-Dec-2011 20:37 by pgaillard

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!! Balloons and blimps
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A balloon can fly very high (50km) and is pretty safe (no explosives involved if it's helium).
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The air weighs about 1.3kg per cubic meter at sea level, so a balloon of a couple cubic meters should be enough to lift a good payload.
Since helium is expensive, it might be tempting to use hydrogen instead.
If a cubic meter at ground level there would be about 50 moles of dihydrogen, which would release about 50*286kJ = 15MJ if inflamed by air and require about the same energy to produce from water.
Version Date Modified Size Author Changes ... Change note
18 04-Jan-2013 13:33 4.556 kB pgaillard to previous
17 04-Jan-2013 13:26 4.379 kB pgaillard to previous | to last
16 22-Mar-2012 09:53 4.018 kB pgaillard to previous | to last
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1 23-Dec-2011 20:37 0.354 kB pgaillard to last
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