Marcus de Sautoy's weights and measures
Discussion
Anyone see this this evening?
If so why did they go to so much trouble to make a perfect sphere? Wouldn't a cube have done equally well and been infinitely easier to make?
And didn't Mr Avogadro know what his number was?
Also Mr de Sautoy, please stop pronouncing nuclear and nucleus as 'nucular' and 'nuculus'!
If so why did they go to so much trouble to make a perfect sphere? Wouldn't a cube have done equally well and been infinitely easier to make?
And didn't Mr Avogadro know what his number was?
Also Mr de Sautoy, please stop pronouncing nuclear and nucleus as 'nucular' and 'nuculus'!
Simpo Two said:
Anyone see this this evening?
If so why did they go to so much trouble to make a perfect sphere? Wouldn't a cube have done equally well and been infinitely easier to make?
And didn't Mr Avogadro know what his number was?
Also Mr de Sautoy, please stop pronouncing nuclear and nucleus as 'nucular' and 'nuculus'!
Yes, very interesting. Can't really believe the chap polished the silicon sphere by hand though!If so why did they go to so much trouble to make a perfect sphere? Wouldn't a cube have done equally well and been infinitely easier to make?
And didn't Mr Avogadro know what his number was?
Also Mr de Sautoy, please stop pronouncing nuclear and nucleus as 'nucular' and 'nuculus'!
Funny bit where they showed the map of all the countries who still officialy use the imperial system - Liberia, Burma and the US.
Simpo Two said:
And if THE holy grail unit of weight is a kilogram, why is it prefixed 'kilo'? That implies that THE unit is the gram...
And the sphere wasn't perfect so the atom count will be inaccurate.
How did we end up siging up to metric anyway? Win to Napoleon after all
As some bloke in the programme complained "we want to stick with good old pounds and ounces and not bother with that complicated kilogram nonsense".And the sphere wasn't perfect so the atom count will be inaccurate.
How did we end up siging up to metric anyway? Win to Napoleon after all
Or as Terry Pratchett and Neil Gaiman put it "It helps to understand the antique finances of the...original British monetary system: Two farthings = One Ha'penny. Two ha'pennies = One Penny. Three pennies = A Thrupenny Bit. Two Thrupences = A Sixpence. Two Sixpences = One Shilling, or Bob. Two Bob = A Florin. One Florin and one Sixpence = Half a Crown. Four Half Crowns = Ten Bob Note. Two Ten Bob Notes = One Pound (or 240 pennies). One Pound and One Shilling = One Guinea. The British resisted decimalized currency for a long time because they thought it was too complicated."
And the £sd system is an absolute doddle compared with ounces, pounds, stones and hundredweights.
The pound sterling remained the same value but was divided into 100 new pennies instead of 240 old pennies. That said, we managed to build the biggest empire the world has ever seen with LSD so it can't have been that difficult.
It dawns on me that we could have done the same with the pound weight - simply divided it into 10 'new ounces' rather than 16 old ones...
Just think... if the Americans had nicked the Le Grand Kilo...
It dawns on me that we could have done the same with the pound weight - simply divided it into 10 'new ounces' rather than 16 old ones...
Just think... if the Americans had nicked the Le Grand Kilo...
Simpo Two said:
And if THE holy grail unit of weight is a kilogram, why is it prefixed 'kilo'? That implies that THE unit is the gram...
And the sphere wasn't perfect so the atom count will be inaccurate.
How did we end up siging up to metric anyway? Win to Napoleon after all
There's a really good video on YouTube that explains why the gram is the only prefixed weight, I think this is it http://youtu.be/ZMByI4s-D-Y but if it isn't I'm sure that's the guy that made it.And the sphere wasn't perfect so the atom count will be inaccurate.
How did we end up siging up to metric anyway? Win to Napoleon after all
Simpo Two said:
And if THE holy grail unit of weight is a kilogram, why is it prefixed 'kilo'? That implies that THE unit is the gram...
And the sphere wasn't perfect so the atom count will be inaccurate.
How did we end up siging up to metric anyway? Win to Napoleon after all
Simpo,And the sphere wasn't perfect so the atom count will be inaccurate.
How did we end up siging up to metric anyway? Win to Napoleon after all
The Gram WAS the original unit of Metric weight measurement, defined as the weight of one cubic centimeter of water at 4C. But in practical life a heavier standard was needed, so that the kilogram became that before the end of the 18th century. We are now standardised on the Metre-Kilogramme-Second version of the Metric system, called the SI system of the International System of Units, which repleced an earlier CGS, Centimeter-Gram-second, system. The values are of course all the same, it's just the unit that is chosen to be standardised.
See: http://en.wikipedia.org/wiki/History_of_the_metric...
Which says that, "Napoleon himself ridiculed the metric system, but as an able administrator, recognised the value of a sound basis for a system of measurement."
As to why a sphere, a cube would have had to have corners that tapered to a single atom to be accurate. Such corners would have been vulnerable to even trivial handling, whereas the sphere may be picked up in the gloved hand without invalidating its use as a standard.
JOhn
Edited by tapkaJohnD on Wednesday 19th June 20:30
tapkaJohnD said:
The Gram WAS the original unit of Metric weight measurement, defined as the weight of one cubic centimeter of water at 4C.
At STP 
tapkaJohnD said:
Which is the answer to
Quite... but if one simply seeks precision, then you can have a precise pound avoirdupois. I also like this because it's English/Commonwealth: http://en.wikipedia.org/wiki/International_yard_an...But maybe nobody can do sums anymore, and they only have 10 fingers. Then again the illiterati may have 12 now; who knows?
Simpo,
have you ever worked with inches? I mean, measured and made items that must fit together? Try measuring something and remembering that it is 3 7/16" long and 4 17/32" wide. 1/32 is the nearest whole fraction of a inch to one millimeter, in fact about 3/4mm.
Now try and remember 87mm x 106.5mm. Now imagine that you want two boxes to fit inside that outer box. Divide 4 17/32" by 2. Easy - 53.25mm.
QED
John
PS the inch parameters I chose at random, not a set up to make it look easy in metric.
have you ever worked with inches? I mean, measured and made items that must fit together? Try measuring something and remembering that it is 3 7/16" long and 4 17/32" wide. 1/32 is the nearest whole fraction of a inch to one millimeter, in fact about 3/4mm.
Now try and remember 87mm x 106.5mm. Now imagine that you want two boxes to fit inside that outer box. Divide 4 17/32" by 2. Easy - 53.25mm.
QED
John
PS the inch parameters I chose at random, not a set up to make it look easy in metric.
Imperial measurements were really inconsistent - fractions of an inch ( 1/4, 1/8, 1/16, 1/32, 1/1000 etc. ), 12 inches in a foot, 3 feet in a yard, 22 yards in a chain ( = the distance between wickets on a cricket pitch ), 10 chains in a furlong, 8 furlongs in a mile ( or 1,760 yards ), 3 miles in a league - all of which made scaling things a real pain.
Not forgetting 1/100th of a chain = 1 link, 25 links = a rod, 2 yards = a fathom, 100 fathoms = a cable, 10 cables = a nautical mile.
Having grown up with imperial weights & measures I can only say that as an engineer SI units are a lot more sensible
Not forgetting 1/100th of a chain = 1 link, 25 links = a rod, 2 yards = a fathom, 100 fathoms = a cable, 10 cables = a nautical mile.
Having grown up with imperial weights & measures I can only say that as an engineer SI units are a lot more sensible
tapkaJohnD said:
have you ever worked with inches? I mean, measured and made items that must fit together? Try measuring something and remembering that it is 3 7/16" long and 4 17/32" wide. 1/32 is the nearest whole fraction of a inch to one millimeter, in fact about 3/4mm.
Now try and remember 87mm x 106.5mm. Now imagine that you want two boxes to fit inside that outer box. Divide 4 17/32" by 2. Easy - 53.25mm.
Actually for length I use millimeters, centimeters, inches, feet, yards and meters, and for temperature, Centigrade below 0, then Fahrenheit from 32 to 212, then Centigrade for 100 upwards! Now try and remember 87mm x 106.5mm. Now imagine that you want two boxes to fit inside that outer box. Divide 4 17/32" by 2. Easy - 53.25mm.
Your fractional example looks harder as fractions than decimals, but for those who did work with them, (having studied fractions at school) they expressed them as lowest common denominator first. 4 17/32" is 4 34/64 and half of that is 2 17/64". Note the numerator stays the same, the denominator doubles. The main trouble with 64ths is they are too damn small to see properly!
And you can of course have digital inches, eighths for example being 0.125, 0.25, 0.375, 0,5, 0.625, 0.75, 0.875. So you still heep the basic unit but divide it up more conveniently in tenths if that's what you prefer. Digital or fractions? Same thing really!
In repsonse to MartG, the imperial system had many units which were not always used, or used in specialist circumstances. Inches, feet, yards and miles are all you really need, depending on scale.
Well I enjoyed the programmes, provides a look inside the world of metrology and how this affects our everyday lives.
The bit that made me laugh was everyone having their photos taken in front of the Le Gran K and the regular checks to make sure it is still there. It really doesn't matter what units are used so long as same one is used, getting it wrong can have serious consequences, the ability to measure repeatably and accurately underpins our whole modern way of life.
The bit that made me laugh was everyone having their photos taken in front of the Le Gran K and the regular checks to make sure it is still there. It really doesn't matter what units are used so long as same one is used, getting it wrong can have serious consequences, the ability to measure repeatably and accurately underpins our whole modern way of life.
Simpo Two said:
SV8Predator said:
How do you pronounce 'nuclear' then?
Without an extra 'u'. Normally only Americans add this.https://www.youtube.com/watch?v=DEYUoISCQ5w
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