Peter Gluck <peter.gl...@gmail.com> wrote: But Cousin, cold water has a greater viscosity! It is excatky the opposite!
Ah, but the cold water comes directly from the water mains a short distance away whereas the hot water goes through the hot water heater at the other side of the house, past the expansion tank, up, around and down to get to the tub. Also, by the time the tub fills up, the water coming from the 50-gallon hot water tank is at tap water temperature; all of the water has been replaced with incoming water. (I have spent a lot time in the crawl space under the house dealing with this plumbing so I recall in detail where things go.) First principles are not always a reliable guide to what happens in the real world. - Jed
