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I understand, that you know the metric system, and, judging by your reasoning for your love for the imperial system, I understand, that you know what you are talking about (better than me). So, please, do not understand my comment as wanting to advise you! It's just, that I found this (on the web, one day) to express so much the way I (having grown up with the metric system) feel about it:

"In metric, one milliliter of water occupies one cubic centimeter, weighs one gram, and requires one calorie of energy to heat up by one degree centigrade -- which is 1 percent of the difference between its freezing point and its boiling point. An amount of hydrogen weighing the same amount has exactly one mole of atoms in it. Whereas in the American system, the answer to 'How much energy does it take to boil a room-temperature gallon of water?' is 'Go fuck yourself', because you can't directly relate any of those quantities."

From: "Wild Thing" by [Josh Bazell](https://en.wikipedia.org/wiki/Josh_Bazell).




Actually, assuming room temperature is 60° and you’re at sea level, it’d take 1,216 BTUs to bring a gallon of water to a boil. A BTU is the amount of heat (which is energy) required to heat one pound of water one Fahrenheit degree; a pound of water is a pint; there are 8 pints in a gallon (2 pints in a quart, 2 quarts in a pottle, 2 pottles in a gallon). So, 8 * (212-60) = 1,216.


1 US liquid pint is defined as the volume of 1.041 lb of water at 62F. The British imperial system is a bit cleaner where 1 imperial pint is defined as 20 oz or 1.25 lbs, at 62F.


"A pint's a pound the world around." I never knew whether that came from the fact that both are 16 ounces or because a pint of water weighs a pound (approximately). I prefer to think it's the latter. Makes it so I can remember that a gallon of water is approximately 8 pounds. 5 gallon pail mostly full, probably 35 pounds. Nice.


Except it's not, as a pint is 20 fl.oz, while a pound is only 16 oz.

UK resident here, in case you couldn't tell :).


You know what is worse than either metric or imperial?

Having both in use simultaneously like we have in Canada, where we work with lots of things manufactured in the US or in Canada for export to the US.

So any technician will have to have both metric and imperial tools, occasionally things of very similar size will get interchanged accidentally - using a 3/4" socket on a 19mm bolt for instance, which will work for a while but eventually round off the head because 3/4" is slightly more than 19mm.


I think we can all agree that mixing systems of measurements is the worst possible thing you can do with measurements. Just ask NASA...

(Look up what happened to the Mars climate orbiter)


And least I forget, because nobody mentioned it, yet, what about the beauty of the DIN A papersize? It has been adopted as an ISO, even! Where everything is simply a half of the previous size.


I suspect that only a minority of people in metric-using countries -- those with basic chemistry knowledge fresh in their mind -- know that "one milliliter of water occupies one cubic centimeter, weighs one gram, and requires one calorie of energy to heat up by one degree centigrade".

Probably a similar number of Americans know the same facts. And any of them would answer "How much energy does it take to boil a room-temperature gallon of water" in the only sensible way -- look up the conversion of gallons to liters, do the calculation in metric, and convert back from calories to whatever unit you want (BTUs, I guess).

The point is: nobody, including Americans, uses the customary system in chemistry labs. Nobody ever has cause to calculate how many BTUs it takes to boil a gallon of water without reference to the metric system. So the argument is a bit specious.


> I suspect that only a minority of people in metric-using countries -- those with basic chemistry knowledge fresh in their mind -- know that

This is not the case. This part: "one milliliter of water occupies one cubic centimeter, weighs one gram" is known by most people, even kids in primary school. In other words everyone knows that a litre of water weighs one kilogram, and that there are 1000 litres in a square metre. I concede, though, that at least in Italy, which is the country where I was born and raised, most people wouldn't know the next part: "and requires one calorie of energy to heat up by one degree centigrade".


"Everyone knows there are 1000 litres in a square metre"

;)


Ooops :-(


You probably meant cubic metre?


Ouch, yes I did


It's common knowledge here; in the UK I was taught it in two classes at school: Science and Cooking.

We are taught to use the scales for measuring ingredients - and thanks to this trick you can weigh water (and milk) and vegetable oil (using 5-10% less) if you don't have a measuring jug.


> I suspect that only a minority of people in metric-using countries -- those with basic chemistry knowledge fresh in their mind -- know that "one milliliter of water occupies one cubic centimeter, weighs one gram, and requires one calorie of energy to heat up by one degree centigrade".

They taught us that in 4th grade in cooking classes. Then they made us remember that in physics and chemistry classes 2 years later.


There are plenty of things that everyone learns in 4th grade that not everyone remembers.


The point is that this particular concept of metric units is taught really well (repeatedly on many practical examples and then evwn theoretical ones) and so virtually everyone knows and uses it. It's deeply ingrained in cooking books, recipes, etc.

Of course I don't remember a lot of things from the 4th grade. This one stands out.


>I suspect that only a minority of people in metric-using countries -- those with basic chemistry knowledge fresh in their mind -- know that "one milliliter of water occupies one cubic centimeter, weighs one gram, and requires one calorie of energy to heat up by one degree centigrade".

I wouldn’t be so certain about that. I’ve used that to conceptualize volumes and weights ever since I first learned that in school.


You comment on HN threads about measurement systems. You are not normal. None of us here are.


Nice point, but it is really the typical elementary school topic "one cubic centimeter of water is one gram, one cubic decimeter is one kilograms, one cubic meter is one THOUSAND!!! kilograms" Then in highschool it is used for physics and unit of measurements and everyone knows that you can just weight milk and water when you cook with 1kg = 1liter


Normal people don’t do that. They just know that a gallon is a gallon, a meter is a meter, a pound is a pound, etc. People rarely have need to convert between mass and volume. And they don’t weigh their milk or water.


Because if they had to, they'd rather find a jug than a calculator.


Also most people (in the US at least) do not have kitchen scales!


We study it in high school.




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