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Ping-pong gun fires balls at supersonic speeds

70 pointsby vinothgopiover 12 years ago

8 comments

azernikover 12 years ago
Web Design Peeve Of The Day:<p>This web site pops up an overlay asking you to subscribe, which you can handily get rid of with a nice big "Close" button at the bottom. Unfortunately, on my netbook (the smallest standard size, but still a standard size) the overlay floats so that the "Close" button is just off-screen no matter where I scroll to. Don't use fixed positioning unless you've made your overlay either really small, or very adaptive to different screen sizes.
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ck2over 12 years ago
The heart of the matter:<p><a href="http://www.youtube.com/watch?v=I9zBGgpzl0I&#38;t=300" rel="nofollow">http://www.youtube.com/watch?v=I9zBGgpzl0I&#38;t=300</a>
tmh88jover 12 years ago
I feel like the schematic is pretty worthless. I thought the picture was mislabeled because the schematic shows the chamber about the size of a two liter bottle, but the picture points towards a ~3' long tube only a few inches in diameter. That, and the nozzle is considerably thicker than the pressure chamber and the diagram shows it as being smaller. I wish I could see an actual schematic (unless they're concealing the design) because this thing is pretty cool and I really would like some details. Imagine what a racquet ball could do in this kind of design (I'm only kidding).
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beaker52over 12 years ago
I'm amazed that the ball leaves circular hole in the bat.<p>I'm no supersonic ping-pong ball physics expert but I'd have expected the ball to have deformed on impact and left an irregular shaped hole and left a more destructive wake than a perfectly ping-pong ball shaped hole.<p>I call fake. But I'm open to being wrong.
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hakaaaaakover 12 years ago
The convergent-divergent nozzle reminds me a little of the design (without the kinks) of a nozzle produced by evolution strategy:<p><a href="http://en.wikipedia.org/wiki/Evolution_strategy" rel="nofollow">http://en.wikipedia.org/wiki/Evolution_strategy</a><p>Video of the evolution:<p><a href="http://www.youtube.com/watch?v=SS2bz3xY71g" rel="nofollow">http://www.youtube.com/watch?v=SS2bz3xY71g</a>
vinothgopiover 12 years ago
I wonder what the ball looks like after it has been fired. Flat? Intact? Or completely blown to pieces.
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kevinbluerover 12 years ago
From the end: "do not, do not, try this at home"...e.g. "do" :)
briholtover 12 years ago
Obituary headline: "Famed athlete, Forrest Gump dies of massive ping pong injuries"