In this ooey, gooey exploration, students experiment with one of the most fun non-Newtonian fluids of all - Oobleck!
Cornstarch and water make a fascinating mixture. For fun, we call it Oobleck, after the Dr. Seuss book Bartholomew and the Oobleck.
The cornstarch is suspended in the water (instead of dissolving like sugar). Stirring it or squeezing it with force causes it behave rather like a solid. When it's handled gently, it behaves more like a liquid. This makes it what scientists call a non-Newtonian fluid.
A non-Newtonian fluid is a fluid that does not follow Newton's law of viscosity. In non-Newtonian fluids, viscosity can change when under force to either more liquid or more solid. Ketchup, for example, becomes runnier when shaken and is thus a non-Newtonian fluid.
What's happening?
Applying a force to the Oobleck squeezes the water out from between the cornstarch bits, so they do not move. Pulling or pouring the Oobleck gently lets the water stay between the cornstarch bits, and they flow with the water.
These activities are part of Science World’s Big Science For Little Hands program. They were developed and tested with preschool and kindergarten educators. Some of the activities are done in stations.
Mysterious Mixtures PDF from Big Science For Little Hands.
