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How do you make this spinning thing? Answered

 Saw this a couple of times and I wanna know how I can make one. I've uploaded a a picture of it so you guys can see it. Thanks a lot.

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steveastroukBest Answer (author)2010-05-25

A Crooke's radiometer
AFAIR there's a vacuum inside the bulb. The little vanes are made of mica sheets, and they're suspended on a needle point.

How's your scientific glass blowing ?

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orksecurity (author)steveastrouk2010-05-25

Actually, there isn't _quite_ a vacuum, as you can tell by looking at which direction the widget spins and thinking about why it spins that direction. (Hint: it isn't the direction it would spin if it was relying directly on light energy.)

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steveastrouk (author)orksecurity2010-05-25

Well, FTFA, "reaches a peak at around 10−2 torr " which is pretty sucky to me ! That 0.01mm of mercury ! You'll not get that from a sharp intake of breath...

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rusheggie (author)2011-01-04

couldn't you make one out of an old light bulb? seal it up with epoxy and use something like a tire stem valve and suck the air out?

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vince 09 (author)2010-05-25

 those things are cool my grandpa has one sitting on his window sill and when the sun hits it, it spins i think he said that the heat or the light causes it to spin, it was a while ago that we talked about it 

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romer_872 (author)vince 092010-05-25

by the way, what's the name of this thing anyway.. 
how do you make one??

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steveastrouk (author)romer_8722010-05-25

Learn to blow glass, well enough to pull a vacuum in it. There is a guy, who I can't find a link to , who is making his own vacuum tubes, which are pretty well what you need to do here. If I find it, I'll post a link.

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romer_872 (author)2010-05-25

 any idea how you can make one yourself??

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