Equalpower (December 31, 1969 at 4:59 pm)

This vid' has been copied way to much... It's cool even though the plate is a bit lopsided. Should be done with better equipment.

than217 (December 31, 1969 at 4:59 pm)

He's a witch!!! *burns at stake*

geshel (December 31, 1969 at 4:59 pm)

The plate vibrates up and down. The places where there's no sand is where it is vibrating up and down the most; the sand all goes to where it's vibrating the least.

geshel (December 31, 1969 at 4:59 pm)

What you're seeing are some of the vibrational modes of a square plate - not exactly sound waves. The sound causes the plate to vibrate, and some frequencies correspond to resonances of the plate. At those frequencies, all the vibrations in the plate "line up" in the patterns you're seeing. At the frequencies in between, not much is happening. That's why the sand seems to "jump" to a new pattern - that's when the next resonant frequency is hit.

sharpyne5 (December 31, 1969 at 4:59 pm)

Crazy !!!!

Ayejaysee (December 31, 1969 at 4:59 pm)

That is so friggen cool

SkunkishMonk (December 31, 1969 at 4:59 pm)

Jesus shit! That's awesome!

Bubesheimer (December 31, 1969 at 4:59 pm)

INTERFERENZ!!!

elanus81 (December 31, 1969 at 4:59 pm)

The patterns do not get strictly more detailed, they just get smaller due to the shorter wavelength (as noted before the spots with salt are the places where these waves cancel each other) if the waves are shorter the distance between these spots is shorter too, so the pattern is smaller, and more of it can be seen on the same plate. I you look into the central shape they reappear like the same note on different octaves.

mechanism8 (December 31, 1969 at 4:59 pm)

Hmm... the paterns become more detailed as the notes go higher, I wonder why? Can any shed some light on this? I'm a little to lazy to google right now... :P