Sunday, November 12, 2006

Fun with semi-solids

If you mix corn starch in water to the right consistency it takes on amazing properties. It can act as both a liquid and a solid, hence the name semi-solid. It can also be called a non-newtonian fluid. If you apply stress to the fluid it becomes solid. If this doesn't make sense perhaps a demonstration is in order.

This is a spanish language video of some performers who made a vat of this liquid and performed some stunts. It's crazy.

What's happening is when they run across the liquid, their feet striking the surface of the liquid causes a localized solid to form and they're able to run across water. But when they walk out onto the vat and then stand, the localized solid turns back into a liquid and they sink in.

Just because they're able to run on water doesn't make them Jesus. Jesus walked on water, not ran.

This next they label "Cornstarch Life Form". It is really a demonstration of cymatics.

Cymatics is a field of science created by a Swiss scientist Hans Jenny. He applied sounds of different frequency to pollens and with a video camera studied the patterns that formed.