Reverberating Polysaccharide

This is a picture of a Non-Newtonian Fluid (made of cornstarch and water) placed on a speaker vibrating at a particular frequency which disturbs the surface of the fluid. A Non-Newtonian Fluid is a fluid that does not have a constant viscosity when disturbed. When it is left alone it takes on the appearance of a liquid. However, when a stressing force (push and/or pull) acts upon the substance, it reverts to a more solid form. A mixture of cornstarch and water is a suspension; the particles of cornstarch are mixed in with the water but remain solid. The water is squeezed out from the space between the cornstarch particles when there is abrupt movement. As a result, the friction between these particles increases radically. The percussive movements of the speaker generate disturbance through the Non-Newtonian Fluid which acts as a medium. The waves travel through the medium and create the finger-like protrusions and cause the mixture to reverberate.

Nick Richards and Jonathan To
St. Elizabeth Catholic High School, Thornhill, ON
Second Prize ( High School Class Category )
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