I suppose using a video camera in any sense of distorting reality doesn’t ring true and is more like a “cheat” than a fail, but this is a rather wonderful, simple and effective demonstration of a sound and water experiment.
You can see more illusions & science videos via Brusspup YouTube Channel.
This illusion is achieved by generating a 24 hz sine wave with the subwoofer and setting the video camera to 24 fps. Result is the camera’s frame rate syncs with the rate of the vibrations of the water so it appears to be frozen or still.
If you play a 23 hz sine wave your frame rate will be off just a little compared to the sine wave causing the water to appear to “move backwards”. Alternatively, play a 25 hz sine wave and cause the water to appear to move slowly forward.
See more posts like this – click