Dancing Cornstarch - Physics Demonstrations - Dancing Cornstarch | Physics Undergraduate Labs

Ensure the plastic sheet is securely fastened and waterproof to prevent cornstarch mixture from entering the speaker cone. Moisture damage can permanently ruin the speaker. Check for tears or gaps before adding the mixture.

Purpose

Demonstrates shear-thickening (dilatant) behavior in a non-Newtonian fluid. A cornstarch-water mixture on a vibrating speaker forms dramatic "dancing" tentacle structures, showing that viscosity can depend on applied stress rather than being a fixed material property.

White cornstarch-water mixture forming peaked tentacle structures on a large speaker cone covered with clear plastic wrap, secured with binder clips, illuminated by a small desk lamp

Same speaker setup with the cornstarch mixture at rest, pooled as a flat white disc in the center of the clear plastic-covered cone; a Pyrex bowl with extra cornstarch visible in the background

Figure 1: The cornstarch mixture "dancing" on the vibrating speaker, forming characteristic peaks and tentacle-like structures as the shear-thickening fluid transitions between liquid and solid-like states.

Figure 2: The mixture at rest, pooled in the center of the speaker cone. When not being driven, it flows freely as a liquid. A Pyrex bowl with extra cornstarch sits nearby for consistency adjustments.

Speaker Cone

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Safety Warnings

Warning: Speaker Protection

Purpose