Amazing Water & Sound Experiment

[rohitmusic]

Amazing!

I have seen this happen with fire.
Amazing with water. Now the Fire element!

Check this Reuben's tube

Similar concept, amazing results!

 

[gobble]

for people trying to figure out what is happening (based on my limited understanding of Signal processing)
http://en.wikipedia.org/wiki/Aliasing
When you have a 23 or 25 hz waveform being sampled at 24 hz, you will see a 1 hz wave.
That is what you are seeing here. The stream is vibrating at 23/24/25 hz, but because of aliasing due to the sampling at 25 hz, it appears to be a 1Hz wave - yes, this is essentially the same reason why the wheels spin backwards on video

Sorry I dont get it - why does that 1hz cause backward spinning again? My head is spinning .... backwards or forwards I'm not sure

--G0bble

 

[greenhorn]

suppose a wheel is rotating at 9 rotations per second. You are filming at 10 frames per second. Imagine a dot on the wheel at the 12 o clock position. The video camera will take a frame every 1 tenth of a second. In the next one tenth of a second, the wheel will have revolved 9/10ths of a rotation, and appear somewhere near the 11 o clock position. Another tenth later, it will appear at the 10 o clock position approximately and so on. The dot will be back at the 12 o clock position after a whole second.

When played back, it will appear as if the wheel is moving backwards at a speed of 1 rotation per second

Now imagine the same thing with a sine wave, and you have this phenomenon.

This is also the reason why the sampling rate for audio has to be at least twice the frequency response needed (44.1Khz for CD's) , because for a sampling rate of f hz, n and f-n hz both appear identical to it, and so to avoid such confusion, it is limited to f/2 or lesser

 

[Santy]

Amazing!

I have seen this happen with fire.
Amazing with water. Now the Fire element!

Check this Reuben's tube

Similar concept, amazing results!

Now that's one hot equalizer visualisation!