The patterns formed in this experiment is known as Chladni patterns or Chladni’s figures. The experiment involves the formation of geometrical patterns when the sand-covered surface is made to vibrate and the sands get collected in the region that has least motion.
This experiment was first introduced by Ernst Florens Friedrich Chladni from Germany.
In the video, sands are sprinkled throughout the metal plate. A tone generator and a speaker are also used for the experiment.
When the tone starts playing, certain frequencies start to vibrate the metal plate in such a way that it leaves some spots where there are no vibration or perhaps, least motion. The sands get scattered into those spots forming geometrical patterns. The patterns depend upon the intensity of frequency, that is – as the frequency increases, the patterns get transformed into more complex ones.
[Video Credit: brusspup]