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As can be noted from the graphs, calculated flow rates was consistently lower than the estimated low rate using the Hagen-Poiseuille equation. However, once the correction was added to the diameter of the tubing in the equation, the data matched much better.

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This experiment confirmed that the Hagen-Poiseuille equation overestimated the actual flow rate and thus was providing an inaccurate estimate. However, the extent of this over estimation was previously difficult to determine. However, what is most interesting is the validity of the tubing inner diameter correction. Using the values calculated from the experiments regarding the tube diameter provided a drastic improvement which makes the equation a better model. Also, because the inner diameter of the tube was 1/8th of an inch, small variation in inner diameter produce large changes in terms of particle movement within the tube and thus head loss and the Hagen-Poiseuille equation. Getting a more accurate image of the inside of the tube allows for the equation to operate more predicatively. Varying tube diameters should be tested to find if these minor inner diameter variations are negligible at larger diameters. Varying tube lengths should be tested to consider the possibility of non-negligible minor head losses.