The Effect of Varying Viscosity on the Accuracy of Bernoulli's Principle

This experiment investigated the effect, if any, that viscosity had on Bernoulli's equation. The experiment used a tube setup with where one section had a narrower pipe. Bernoulli's law states that if a liquid is flowed through a closed pipe system through different width pipes, then the liquid will have a higher velocity in the thin pipe and also a lower pressure. The law assumes that there is no internal friction, viscosity. This is an incorrect assumption, because all liquids have a viscosity. The experiment tested three different liquids one with a low viscosity, rubbing alcohol, one with a high viscosity, soybean oil, and water, which has a moderately low viscosity. Unfortunately the rubbing alcohol caused the Plexiglas pipes to split, and the rubbing alcohol variable was removed from the experiment. After running several t tests, the data showed that this experiment did not uphold Bernoulli's principle because both tests returned P-Values of nearly zero. Furthermore, a two sample t test showed that the water and the soybean oil data were statistically significantly close with the P-Value of .35. Therefore, this experiment concluded that experimental errors caused Bernoulli's principle not to be upheld under these testing conditions, and the difference of viscosity in water and soybean oil did not cause the water and soybean oil data to differ significantly.

Research Done By:

Brandon Long
Cousino High School

Preston Render
L'Anse Creuse High School