B Temperature-Dependence of Viscosity of a Fluid?

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The discussion focuses on the relationship between temperature and the viscosity of fluids, specifically glycerol, and its effect on the terminal velocity of a sphere falling through it. The user seeks clarification on the constants A and B in a temperature-viscosity equation, which are described as 'fundamental constants.' There is a suggestion to refer to a Wikipedia article on the temperature dependence of viscosity for more information. The user questions whether they are overcomplicating the approach to understanding the temperature dependence of terminal velocity. The conversation emphasizes the importance of understanding these constants for accurate calculations.
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What does the Andrade equation for relating viscosity and temperature actually show?
Hi all,

I was looking into how the temperature of a viscous fluid (glycerol, for instance) affects the terminal velocity of a sphere falling through and deriving a mathematical relationship. I know that the viscosity and terminal velocity can be related through Stoke's law, but had a bit of trouble with the temperature bit.

I found the following equation:
Screenshot 2025-05-01 at 5.09.13 PM.png

But couldn't find any info on what A and B actually are, apart from being 'fundamental constants'. What exactly are those constants, and how do I find their values for certain fluids? Or are I overcomplicating this, and shouldn't be using this equation at all for finding the temperature-dependence of terminal velocity?

Thanks!
 
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