Trippy sciencey video of the day: Static flow of water using sound
You’re actually seeing 25 different drops [or segments of the stream] every second… the waveform being played through the speaker is vibrating the pipe in a uniform way, so the drops exit the pipe uniformly, the frame rate of the camera is synced with the speaker so the drops appear static, [and] the short shutter speed means the drops appear sharp and frozen in mid air [a longer shutter speed, in contrast, would capture more of each droplet’s movement, causing it to appear blurry].
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