It’s no secret that Bram Cohen thinks that most peoples

It’s no secret that Bram Cohen thinks that most peoples’ perception of BitTorrent is far too narrow. He’s got to be thrilled, then, about the fact that his company’s new peer-to-peer live streaming app is now ready to show the world the kind of content delivery torrent technology is really capable of handling.

After a four-month closed testing period with several key partners (like the Internet Archive), the BitTorrent Live open beta was announced this week at SXSW. It works how you’d expect torrent-based broadcasting to work. One person (the broadcaster) puts up the initial stream. As additional viewers join in, they become seeds and help distribute the load across the network.

For smaller broadcasters looking for a way to reach a bigger audience without impacting their in-house bandwidth too much, BT Live may be a good alternative to other streaming options. Perhaps not so much for individuals who can live stream with apps like uStream and YouTube, but certainly for indie broadcasters that might otherwise have considered using something like Brightcove’s cloud service.

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The first thing every kid does with a hose when they pick it up is the same

The first thing every kid does with a hose when they pick it up is the same. You put your thumb on the spout and bend the stream to your will. If you grow up and take that one step further, you could come up with something pretty fantastic.

Optical illusions come in all shapes and sizes. Typically, when you think of optical illusions, most people think of perspective based image manipulation. It’s not often that a constantly moving object generates such an illusion. It turns out, this has a lot to do with how fast things move. If you catch them at the right frame rate, constantly moving objects can deliver similar optical illusions. This video is an example if such an illusion, capturing flowing water as it the spout it is pouring from is subjected to specific vibrations and then captured at 24 fps.

In this video, the vibrations from the speaker cause the tube to vibrate in a very specific pattern. This, in turn, causes the water to leave the tube in that same pattern. The different patterns captured here are a result of the tube vibrating at 23hz, 24hz, and 25hz while being captured on camera at 24fps. If you were to conduct this experiment yourself and you were just looking at the water with your eyes, you wouldn’t see the sine wave patterns that are captured by the camera. Our eyes capture the world at significantly faster than 24fps, so the camera serves as an interrupt that allows us to observe this optical illusion.

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Engineer Mehdi Sadaghdar makes YouTube videos in which he answers questions about electronics and technology

Engineer Mehdi Sadaghdar makes YouTube videos in which he answers questions about electronics and technology. One question he apparently gets quite often is which type of electricity hurts more, AC or DC? You have to respect the commitment Sadaghdar has to his audience. To answer the question, he applied increasingly potent electrical shocks… to his tongue.

In AC, or alternating current, the flow of electrons periodically reverses. DC (direct current) is simply unidirectional flow of electric charge. Most electrical systems in the world run on AC (50-60Hz), but many devices require DC power. In these cases, a power supply steps the power down to DC. If you’re tinkering with electronics, there are plenty of places you could get a nasty jolt from either form of electricity.

Sadaghdar wanted to figure out which type of shock would be more painful, but without using huge (read: dangerous) amounts of voltage. It stood to reason he should use the body part with the lowest resistance, which turned out to be his tongue. There are a few incidents during the testing process, which should serve to remind you not to try this at home.

With DC, Sadaghdar started at 1 volt and ramped it up to 12 volts, where he was forced to stop. Before the actual AC testing got underway, Sadaghdar demonstrated how the frequency of AC causes the muscles of the tongue to contract. It’s an effective visual aide. As for how painful 60Hz AC is, he had to stop at about 6.5 volts.

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