Is the US fluid ounce the same volume as the Imperial fluid ounce?
The US fluid ounce is the same as the Imperial one - the amount of water that weighs an ounce. There are 20 fluid ounces to an Imperial pint, but only 16 in US; there are eight pints in a gallon in both systems, but since the size of the pint is different, the size of the gallon is therefore different. I do not know why the decisions were made, but the 16 fluid ounces in the US pint of water weigh one pound; whereas, as every English schoolboy used to know before we were infiltrated by the evil French system, in the Empire a pound of water weighed a pound and a quarter.
Asked on 15 December 2010 by DS, Houston, Texas
Answered by
Honest John
Many thanks. Another reader referred me to the Wikipedia entry that shows the derivation to be the measure for a gallon of wine v/s the measure for a gallon of ale (which presumably accounts for expansion). We use the ale measure. The Yanks use the wine measure.
Tags:
fluids
Similar questions
Must the engine be running while checking power steering oil level?
There is an unidentified fluid leakage in the engine bay of my Volvo V50. Towing the caravan home on a hot day I thought there was a smell from under the bonnet. Looking into the engine bay from the front,...
My 2008 Citroen C5 Tourer is leaking fluid. The leak is inline with the front wheels, but more on the driver's side. The fluid drips like water but has a oily texture to it with very little smell. Should...
Elsewhere on 
.jpg)
