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Incredible optical illusion freezes gravity with sound

first_imgSound waves can do some wildly divergent things, from delivering music to your ears, to mapping the ocean floor, to making it appear that the laws of physics have been suspended. YouTube user Brussup filmed a simple experiment that will bend your mind and make you call fake, at least until you hear how the trick is done.The setup in the video is simple. A supply of water is atop a subwoofer and allowed to leak slowly down past the front of the speaker. The subwoofer is used to output tones of 23 and 24Hz, which produces an astounding effect. These tones cause the water to appear to be frozen in mid air, or even to flow backwards in the video.The secret is that the camera used to film the effect has a frame rate matching that of the tone. When set to 24 frames per second, the video frame rate is synced with that of the oscillation of the water drops if the subwoofer is outputting 24Hz. That makes the water drops look like they are suspended in mid-air. If the tone is dropped to 23Hz, the video is slightly out of sync, and the water appears to flow up into the spout. Brussup’s video description also states that a 25Hz signal will make water appear to flow downward in slow motion.Of course the actual water is still behaving normally — it’s just the video that displays the effect. But that doesn’t make it any less mesmerizing to watch. It really looks every bit as good as any example of Hollywood computer generated magic.You can try this experiment yourself with very little equipment. Surely you could use this to make your friends and family think you are a wizard of some sort. Who ever said the Internet wasn’t useful?via TheNextWeblast_img read more