"Oobleck" still holds some surprises

Oobleck, a mixture of corn starch and water that behaves as a liquid when stirred gently but hardens when struck, has revealed new surprising properties through high-speed imaging and force measurements. This non-Newtonian fluid changes viscosity in response to applied forces, similar to ketchup and yogurt, straddling the boundary between liquid and solid behavior. Recent research published in Physical Review Letters demonstrates that oobleck drops hitting surfaces exhibit unexpected characteristics, highlighting the complex physics underlying this seemingly simple substance.