If you want to keep people alert, what about degrees Rankine?
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3 years ago
It was fifty years ago today (well, yesterday)
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3 years ago
Neither are particularly sensible, as that the freezing and particularly boiling points of water can vary considerably with variations in pressure. Yes, I know that they are defined at Standard Pressure, but that means that you also need an accurate means of establishing the pressure.
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3 years ago
And a litre weighs a kilo ...
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3 years ago
And, even more important, a cubic centimetre weighs a gramme or a cubic decimetre (a litre) weighs a kilogramme or a cubic metre weighs a tonne. There you have a nice simple relationship between linear and volumetric measurement. What's the equivalent conversion factor for imperial? A UK gallon is 277.419 cubic inches. Not a nice round number. Not even an integer. Duh! What were they smoking when they came up with that?
Many years ago my dad and I were installing a hot water cylinder at our holiday cottage. We had no calculator and only a tape measure calibrated in inches. We wanted to work out how heavy the cylinder would be when it was full of water to decide what thickness of timber we needed for supporting it above the stairwell. Volume is pi r^2 l. For the sake of an approximation, take pi is being roughly 3. We calculated the volume in cubic inches. We knew the the approximation that "a pint of pure water / weighs a pound and a quarter" or a gallon weighs about 10 pounds. But neither of us knew how many cubic inches were in a gallon - not even roughly.
I ended up converting the linear measurements to centimetres (using the approximation of 1 inch is roughly 2.5 cm), getting the volume in cubic centimetres, getting the equivalent weight in grammes - and then converting back to pounds because dad could "visualise" a weight in pounds better than one in kilogrammes. All because we didn't know how many gallons (ie tens of pounds) corresponded to the volume in cubic inches.
We'd have done better to have walked up to the phone box half a mile away, read out the figures and get my mum to do the calculations. She may even (long before Google) have managed to find the cubic inch / gallon conversion factor in a book somewhere, to save conversion to/from metric. But it was pouring with rain so we couldn't be arsed to get in the car to go to the phone box.
(We judged that a couple of baulks of 2x4" timber would be good enough, and
40 years later the cylinder hasn't fallen down the stairwell, so we evidently erred on the side of caution.)- Vote on answer
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3 years ago
But IIRC our US cousins are traditionalists. They are using the imperial measurements from independence times. It was the UK that changed them later.
Surely you, being against aligning with any other countries, approve of this?
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3 years ago
Only of water. a cubic meter of gravel weighs 3 and a bit tonnes
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3 years ago
Cold end was based on a year in Danzig and the coldest it was, and was redefined several times. 100 was human temp, but again was redefined.
The nice thing about it is that 0 is bloody cold and 100 is bloody hot. Air temperature wise
Given the tools and techniques available I still think its a damned sight better scale fore 'weather' than Celsius.
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3 years ago
No, it isn't. Nothing in the real world is yes or no.
50 shades of grey is what we have, and Boolean logic is entirely a human mental invention designed for simplicity with no regard for accuracy.- Vote on answer
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3 years ago
No it doesn't. About 1.6 tonnes.
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3 years ago
The UK did not change and the US was not more traditionalist. There were many different gallons and the US and UK just happened to standardise on different ones.
The UK standardised (roughly) on the Ale Gallon, while the US standardised on the Wine Gallon - both of which were one of many different gallons used in the UK until they were abolished by the 1924 act.
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3 years ago
and what about Reaumur?
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3 years ago
Which had existed for a century when Celcius proposed his scale. He set
100 as the freezing point of water and zero as the boiling point at the mean atmospheric pressure at sea level. The scale we know as Celcius today is actually the reverse of his.- Vote on answer
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3 years ago
and The Kelvin scale is set as 0K to be the triple point of water where it exists in 3 sates of matter (solid, liquid & gas) all at the same time, which is about 0.4 °C IIRC.
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3 years ago
But has used a decimal currency for a long time! Which is what was being discussed. Do keep up!
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3 years ago
Ok pedantry time ...
... only when you specify the material, Water, and the temperature (20C?), and pressure (dunno), and maybe other stuff?
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3 years ago
And a litre wieghs a kilo..... a kilo of what? Kilo is a prefix meaning
1 thousand, which is a number, and you have not stated the *exact* measure....For all I know you could be talking kilowatt, kilometre, kiloOhms, Kilofarads or KiloHenries.....
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3 years ago
Kelvin and Rankine don't have degrees - they're absolute.
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3 years ago
Fahrenheit has had a bad, bad, press over the centuries
It was, after all, the ORIGINAL centigrade temperature scale.
Celsius was a relatively late-coming plagiarist !
PA
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3 years ago
It may have been centigrade, but those hundred degrees were relative to random temperatures (the coldest and hottest that Fahrenheit could achieve). The freezing and boiling point of water are easier for a layman to understand than the freezing point of saturated brine or whatever was used for 100. OK, so freezing/boiling of water are fairly inexact, and will vary according to pressure, and impurities in water.
I've always wondered: why is it that F and C are denoted as "degrees F/C" whereas Kelvin (like all other physical units) is just "Kelvin" (not "degrees Kelvin")?
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3 years ago
Sometimes the colloquial and the scientific don't always align.
No amount of logic to the metric system is going to make it easier to say "568ml please" rather than "a pint please".
And as noted in this thread, most people just say "2x4" in the same way they'd say "the blue one".
I really struggled to understand that some people failed to grasp that there can - and often is - a difference between what you measure in, and what you call things. To the extent I suspect a lot of them are putting more effort into being dim than clever.