A Wierd Demonstration of Sound Energy!

As you saw in the vintage video about sound and waveforms, sound is conveyed by pressure waves in the air, produced by some vibrating source and reaching our ears where it causes the ear drum to move--and the movement there generates signals to our brains. Very loud levels of sound carry so much energy that they can damage the structures in human ears. Here is a demonstration of sound energy and its effect on a common substance (cornstarch and water) which has some very unique properties as a "non-Newtonian" fluid--a slushy subtance that normally acts like liquid but under pressure acts more like a solid. This demonstration produces some very wierd effects just using sound energy. The "mush" is placed into an ordinary loudspeaker and a sound at 30 Hz (kind of a very low rumble) is played by the speaker. Everything that the cornstarch mush does here happens because of the sound energy that is being pushed into it--it is NOT alive even though it looks like aliens.

Here is another video demonstrating that same "non-Newtonian" substance, but lots of it! This next video has nothing to do with sound but it's such an unusual thing that I figured you might find it interesting after seeing how wierd that cornstarch acted above! What's happening here is that these people have filled a large tub with mixture of cornstarch and water. This kind of substance reacts as a solid when hit with pressure--such as feet striking the surface of it--but when not hit with pressure it acts like what it is: mush! Worth watching just because the phenomenon is so unusual! Watch them run across it like Christ walking on water but sinking like Peter when they stand still!