Displaying fractions of inches

And here are TABLES from NIST

When silver pennies were first introduced into England, their weight was 24 grains, which would have made a penny's weight a pennyweight.

and the SI unit of mass is the Kg.

First off, the unit of mass in the US is the slug. (Not very poetic, is it?) An object with a mass of one slug exerts a force of 32.17 pounds on its support.

Or you could use the poundal. Or even the lb mass. While it is true that a great many errors are made in unit conversion, that is not the exclusive province of imperial units of measure, and a few of us old farts have figured out how to do our work correctly without metric units.

Technically the metric system was the first legal system in the US - courtesy of Thomas Jefferson, who had it enshrined in US law as a legal system for weights and measures. This was a couple hundred years ago, so don't tell ME the US lags behind the world in going metric!

Oh, and there is no country in the world that is truly 100% metric. If you examing the dimensions of I-Beams or pipe in Great Britain, you will find they convert to exactly the same piece of iron as the old "imperial" standards. I'll never forget the time in the late '70s when I did a presentation for some engineers from Mitsubishi Nagasaki Machinery. The interpreter stuck up her hand, and asked "Please sir, they want to know what is a Pascal?" I went immediately to psi and they knew exactly what I was talking about.

I like many things about the old imperial units. For example, I can more readily delay that exercise program by telling myself "My weight isn't that bad - it's under 15 stone."

The US can get away with not being metric because our economy is so large. Don't kid youself - if the costs of not going metric exceed the cost of converting, we'll go metric. That's a decision every company makes for itself in our system. Look at the automotive industry for example.

Peter, I was going to comment that responses to your query were a bit sluggish but Tom beat me to it.

One of my favorites it is getting force readings from european companies that are in kg. The brits are great for that... Here's an example

http://www.sciencescope.co.uk/Force_Meter.htm

Mass and weight

Peter:

Don't think that, simply because no one responds, it means that no one knows. Looks like several of us know. I got beaten TWICE!

Maybe.

Part of the confusion comes from the language itself. We say "This lump weighs one kilo", when we really should be saying either "This lump masses one kilo" or "This lump weighs 0.102 Newtons" (depending on just where on Earth you are).

Language is almost always more a matter of habit rather than precision. So one day, we'll order a "pint", and get 500 mls of brew. (which should make everyone happy (except the barman - but he'll just jack up his price to cover the cost of the extra 25 ml).

And to answer your question: "Pound" is the British unit of weight. "Slug" is the (incredibly obscure and Trivial Persuit answer for the) British unit of mass.

Originally posted by gbradley

Is there a difference between mass and weight here on Earth?

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If you've ever pushed a boat from the dock, then you'd know the difference. You can get a very large mass to move horizontally, but you'd never be able to move it veritically (away from the Earth's force).

Inertia is where you start to worry about mass, which is the point of what Peter is ranting about saying.

As the previous three posts point out to varying degrees there are probably as many individuals in 'metric' countries that know the correct units of force and pressure in the SI system as there are individuals in the US that know the correct imperial unit for mass. OK, maybe I'm exagerating a little bit. However, simply because a measuring system is based on a factor of 10 (which is why people get such a chubby about the metric system) doesn't automatically mean it will be used correctly.

So, how many kilograms do I weigh, anyhow??

Keith

kamenges said:

So, how many kilograms do I weigh, anyhow??

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This reminds me of a joke my kids are fond of:

How you get down off an elephant?

You don't. You get down off a duck.

---

So it's not "How many kilograms do I weigh?", but "How many kilograms have I amassed".

Quick, back-of-the-envelope conversion: Take your weight in pounds, divide it by 2, then knock off 10%.

Quick, back-of-the-envelope conversion: Take your weight in pounds, divide it by 2, then knock off 10%

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Sounds like how Doug and Bob Mckenzie do metric...

"Double it and add 30" (not exact although between 0 and 40 C you get no more than about 5 deg (F) deviation... amazing)

now, let's all line up alphabetically by height.

I expected Tom, Norm, Allen and Steve to have these answers. Tom gave a good good answer. My mass transfer and energy provide 3 different ways of indicating mass in British units. This only proves a point the British units are confusing.

Allen, I didn't say that know one knows. There is a question mark there. I was just taunting a bit, but with a purpose of drawing out some good information.

Now we can have that 500 ml of beer.

So we Ship and receive goods in 20 foot and 40 foot containers.
What do you call them 6 Meter and 12 Meter containers?

gbradley said:

So we Ship and receive goods in 20 foot and 40 foot containers.

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You might have guessed that I would reply to that quote George, But I have to correct you on container sizes..

Now a 40 foot container is actually 40' or 12.035M (exterior measurement), but a 20 foot container measures 19 foot 10 and 1/2 inchs (19'10.5"), that's 2.339M

Paul

PLucas said:

Now a 40 foot container is actually 40' or 12.035M (exterior measurement), but a 20 foot container measures 19 foot 10 and 1/2 inchs (19'10.5"), that's 2.339

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Another victory for the error free metric system.

Or maybe not. My calculations show 19' 10-1/2" = 6.0579 meter. It shows 40' 0" as 12.192 meter.

12.035M = 39' 5-13/16"
2.339M = 7' 8-3/32"

(Gosh, I love being a smart a$$)

And remember THIS GREAT TRIUMPH of metric->english conversion

Looks like it is a little late for me to chime in. I agree with everyone else. (Damn, that's what I get for waiting to check the forum!)

and what moron came up with the term slug?? I never did understand that one.

I agree with you bernie. If we all used the same terms, things like this are less likely to happen.

Yea I was gonna direct the question to Paul, but you hadn't previously posted.

So do you call 'em 20 footers?