Testing Viscosity - Calculations

I wanted to convert my findings to one of the traditional units for viscosity, either centipoises or Pascal-seconds or Slugs/foot second, or degrees MacMichael so I found this formula to help.

It is a modified configuration of Stoke's Law.

I found it on a University of Hawaii page, a University of Madison, Wisconson page and in other places.

The first viscosity I tried calculating was that of water.

I plugged my values for water in, including the density of the water, the density and the speed of the ball.

A little math...
I converted the disparate units to centimeters, grams and seconds.
I cancelled out some centimeters on the top.
Close to an answer.

I got stuck at this point and consulted a real scientist & cockeyed.com supporter, John O'Meara at the Center for Astrophysics & Space Sciences at UCSD.

He was operating without the benefit of Goldschlager, but coaxed me forward in my calculations.

Clearing more units.
I arrived triumphantly at an answer! 1.095 g/cm-s or 0.1 kg/m-s. This is the correct format for an answer, but the well-documented viscosity of water is actually .001 kg/m-s.

John arrived at the same numbers and was as perplexed as I am.

I seem to be off by a factor of 100.

I used this technique to calculate the incorrect viscosity for the eleven other liquids too.

The viscosity results spreadsheet

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Last updated March 9, 2003.

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