Amplified Oobleck
Question: Which amount of vibration, specifically Hertz levels from an amplifier playing music will cause the most movement/dancing in the non-newtonian fluid when it is placed on the amplifier?
Hypothesis: We think the non-newtonian fluid will react/move the most when the music is a loud bass vibration. We think this because the bass gives out the most concentrated vibration out of all of the three music sounds played including mid range and treble because of the pressure of the Hertz levels of Bass.
Our Experiment
Materials:
Materials
Corn Starch, Water, Bowl Spoons, Measuring cups, paper towels, saran wrap, amplifier, electrical outlet and extension cord, masking tape, smocks, hand wipes, and garbage bags. Three small bowls and three spoons for attendees. |
Safety ProceduresInform participants that the solution may stain clothes so please wear smock. Keep solution at table.
Material 1: Do not eat the cornstarch solution, do not throw or get it in eyes on face. Do not put oobleck down sink. Material 4: No water near the electricity or amplifier. |
Procedure:Detail steps so anyone can reproduce this at school or home
Use a numbered list
Special Needs: Electricity/sink Quiet Room, music from amplifier is loud and may disturb other experiments. |
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The Science behind it
Non-Newtonian fluids change their viscosity or flow behavior under stress. If you apply a force to such fluids (say you hit, shake or jump on them), the sudden application of stress can cause them to get thicker and act like a solid, or in some cases it results in the opposite behaviour and the molecules may loosen and become more of a liquid than they were before. If you remove the stress (let them sit still or only move them slowly) they will return to their earlier state.
One non-newtonian fluid called Oobleck is a suspension of cornstarch and water that can behave like a solid or a liquid depending on how much pressure you apply. Oobleck is a suspension, not a solution. The cornstarch does not dissolve in the water like salt or sugar would. Instead, the tiny starch particles are suspended in the liquid. If you let it sit long enough in a glass, the cornstarch will settle to the bottom leaving a layer of clear water on the top.
The most generally accepted explanation for the behavior of Oobleck is offered by Cary Sneider in “Oobleck: What do Scientists Say?”. When sitting still the granules of starch are surrounded by water. The surface tension of the water keeps it from completely flowing out of the spaces between the granules. The cushion of water provides quite a bit of lubrication and allows the granules to move freely. But, if the movement is abrupt, the water is squeezed out from between the granules and the friction between them increases rather dramatically.
When a fluid’s viscosity is constant it is referred to as a Newtonian fluid. Oobleck is an example of a fluid whose viscosity is not constant, it changes depending on the stress or forces applied to it. If you poke it with your finger and apply a large force, it becomes very viscous and stays in place. If you gently pour it, applying little force, it will flow like water. This kind of fluid is called a dilatant material or a shear thickening fluid. It becomes more viscous when agitated or compressed
Conclusions
In conclusion, the bass made the oobleck dance the most. We learned that the closer the oobleck is to the speaker/pressure the more the oobleck will dance. It danced the most to the bass frequency which is 20 to 400 Hertz ranges. Rock and Roll music made it dance the most because of the loud and frequent bass vibrations. We first placed and observed water on the saran wrapped speaker and tested all music levels and the water vibrated the same with all Hertz levels bass, midrange and treble. The oobleck molecules piled together to bass only.
Nathan |
Brunon |
Charlotte |
