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Sorry, how do you get water vapour at 0’C?
Never seen vapour coming off of ice?
Ooo.... and snow and hail forming in clouds. In fact... clouds.
For me, being in my 40s I grew up with both, metric via school and imperial via (grand)parents.
Weirdly for me it's the other way around. But then my grandparents lived in (mostly) Europe c/o Foreign Office, and I always recall my grandmother talking "kilos" in the kitchen, with metric scales, and my mother always "pounds/oz" or volumetric measures of food, probably due to being in boarding school.
Certainly odd when I come across people younger than me that convert petrol price to gallon prices, and will never have seen fuel sold in gallons or pence per gallon, and probably young enough to have never seen orange squash sold in gallon containers either. I can only assume they're in the JRM mob when it comes to putting mpg and pence per l in to unified measurements.
Least a l is well defined. When talking gallon there's at least 2 different ones, and one can only make a guess as to which is meant from the accent.
Never seen vapour coming off of ice?
Huh. Good point. Funny thing, Physics.
In fact… clouds.
I thought one of the metrics was "at sea level pressure"?
When talking gallon there’s at least 2 different ones, and one can only make a guess as to which is meant from the accent.
Yeah, those Texans with their 8.3-gallon hats.
I thought one of the metrics was “at sea level pressure”?
Yeah, that was going off on a tangent. Sorry.
Stick with sublimation... even if it is nowhere near as interesting as the crazy cloud stuff (which I freely admit to not really understanding anyway).
The most ironic fact I ever learned about Metric and Imperial is that the bastion of inches and ounces that is the US of A defines the inch and pounds and ounces etc by metric equivalents.
But contrarily, kph is idiotic. the per hour introduces a 3600 which is definitely not helpful for anything.
Humans broadly understand speed, distance and time using km/h and mph to the point that in less densely populated places like Australia (and presumably US and Canada) people refer to distances in travel time (How far to Coffs Harbour - about an hour and half). Only NASA measures speed using seconds. Oh and probably Tesla cos they and their owners are special.
There have been attempts at metric time.
Never seen vapour coming off of ice?
That's not the ice vaporizing, that's water vapour in the warmer air condensing as it comes into contact with the colder object. Same as the steam you see coming out of your kettle isn't water vapour, it's the vapour condensing into liquid droplets in the cooler air.
The triple point of water is at 0.01 C, but only at a specific pressure too - so it doesn't happen on the Earth, in natural circumstances. The altitude on Mars is measured from where the atmospheric pressure is that triple point pressure - above this altitude water sublimates from solid to gas, with no liquid phase.
There have been attempts at metric time.
Until fairly recently Kodak used the metric calendar internally.
You are talking about observing something other than sublimation Mike… both happen. You’re right that it’s the suspended condensing vapour you see though, in both cases.
Damn… that means, in full pedantry mode, that none of us have actually seen water vapour coming off of ice… only observed the effects of it.
My brane hurts.
in less densely populated places like Australia (and presumably US and Canada) people refer to distances in travel time
In my anecdotal experience the US definitely does, often to the exclusion of even knowing the actual distance. I've had this conversation more than once:
"How far is it to town?"
"About an hour."
"But how far is it?"
"About. An. Hour."
"Yes, but what's the actual distance?"
*looks at me like I'm a crazy person*
UK TV news does the same now. Car culture.
in less densely populated places like Australia (and presumably US and Canada) people refer to distances in travel time
Surely most of us do that? There's a reason Google Maps shows the quickest route first, not the shortest.
A kilo isn’t ‘about the same as a litre,’ it’s exactly a litre
needs the purity of the water to be specified if you're being exact.
/nitpick
I was told at school that water vapour is visible.
Steam is a gas and isn't.
However I went to an Imperial school - but never got to be a Stormtrooper.
Are we comparing to the original kilo, litre etc?
/nitpickier
If you go to a tool shop in the most metric country there is & ask for a 19mm socket, I bet it still has a 1/2" drive.
I was told at school that water vapour is visible.
So was I. But it never goes well when you tell other people that. I’ve had to accept since that ‘water vapour’ is the invisible (in small quantities at low density) gaseous water, rather than a mix of gas and condensing droplets. Where as steam is a visible vapour (made visible by the droplets suspended in it). Our teachers confused us. Even if there were right and the rest of the world is wrong. Still find it hard to shake of their teaching though… to me a vapour and a gas are clearly defined… but “common usage” has warped their meaning when referring to water.
The most ironic fact I ever learned about Metric and Imperial is that the bastion of inches and ounces that is the US of A defines the inch and pounds and ounces etc by metric equivalents.
The US were early adopters of metric and decimal - Dollars and Cents for instance rather than our slightly bonkers Pounds / Shillings and Pence and the extra weird Guinea (base 21 - nice)
They didn't proudly uphold Imperial measurements - they tried to implement metric and cocked it up. In the UK we set a date and said from that point on for given transactions they must be done in metric. In the US they did the same thing but instead of 'must' it was 'should'.
If you were a shop keeper you were told you 'should' change your weights and measures - that might mean printing up new signage. If you went to that expense and your competitor didn't then you felt you were at a disadvantage. So nobody did. Within a few years of course everyone has reprinted their signage so it was all moot, But by then the moment had passed.
They also didn't have Max Bygraves
At 61 my secondary school years were 1970-1977 and I'm pretty sure we were taught using metric/SI units. I grew up on a farm and sometime around the late 1960s remember there being conversion tables for acres to hectares and the like since the government subsidies were moving to metric. I honestly can't remember the last time I heard a farmer talk about the weight of an animal in anything but Kg.
I'm ambi-system about most things so bigger distances will go: 100m, 200m, 400m, half a mile, a kilometre, one mile, two kilometres, etc. I'll just choose the closest convenient measure.
EXCEPT - temperature. Fahrenheit is just a bodge of a system and I really can't get my head around it or why anyone would want to use it.
I listen to a US cycling podcast and they are 50/50 between imperial and metric and will usually convert one to the other as well. Their race analysis videos also have speeds displayed in mph and kmh. Obviously World Tour road cycling is European centric so races, speeds and the like are metric so using it makes sense in that regard.
@Cougar - a lot of places "measure distance" by time, makes a lot of sense when the roads are less than ideal and actual speed on the ground is highly variable.
I can't wait. FASL will offer more precision than MASL so my coffee will taste even better!
Water vapour can be below 0C if it's mixed in with other gasses like air, it's to do with partial vapour pressure.
But air can be super-saturated with water vapour if there aren't any nucleation sites to attract condensation. Hence dew and frost.
I (50 plus years and still handsome) work in metric for measurements except for long journeys where I use miles to avoid confusion with most other people in England.
My wife (a touch older and still gorgeous) uses imperial.
When working together we use the universal body part measurement. "Move it a fat thumb this way", "Stick your hand above your head and nail the wood there", "Take three baby steps and plant the tree facing the sun".
Thankfully we are not engineers and few things we do together are life critical.
Ooooh Engineering "measurements"
1. A midges dick -approx 3 thou..
2. A nudge - approx 1/4 inch
3. A shove - approx an inch
4. Give it a nip - approx 5 ft/lbs
5. Dog it up - stop when it squeals
4 and 5 are not euphemisms
I just hope it applies to shocks, I've still got a few in the old sizes to sell which got randomly obsoleted by the change to metric