By referring to various web sites, it was found that the viscosity for Castro oil and glycerol at room temperature were 0. 65 and 1. 0 NSA/AMA respectively. The discrepancy between the theoretical and the experimental results could be attributed to one of the following reasons: The time recording methods for dropping the spheres into the liquid was imprecise The measured spheres weight was inaccurate The length of the flask was not quite sufficient for the sphere to reach to the terminal velocity needed for settling.
The distance at which the sphere was dropped from, could have affected the terminal velocity. By doing a reverse engineering calculation using the equation given in the lab sheet for Castro oil (0. 65 NSA/AMA ) , it appeared that the time needed to get this viscosity could reach to about 12 seconds. This was quite impossible in our experiment to be obtained. Accordingly, one possible Justification for this problem could have been the liquid unknown type, which we assumed to be Castro.
The experiment objective in principal was achieved and many new techniques were learned and developed. Finished completely. All the record result were fine but with some error percentage suitable to some different factors, one way is to drop the peeress Just above the surface to reduce the increase in velocity, also the errors can be minimized by recording the timings precisely and increasing the number of repetition of the time recording to get an accurate average.
Even though doing these methods to reduce the error percentage there will still be some minor errors. This experiment developed our way of thinking and knowledge, where this experiment is a minimized example for the velocity of different types of fluids in pipes due to its viscosity and the floating of liquids above water or under water due to its density.