Any tricks to thinking in meters than feet

[Steve Smith]

Though I would rather pay $3.09 for an imperial gallon, than a US gallon...

I would like to pay that for a US gallon... or even half a US gallon. Petrol here is about £6.22 for an Imperial gallon, that's about $9.73. Our equivalent price for a US gallon would be $8.11. Yet it's strange that Americans seem to be the most vocal about their 'high' gas prices!


Steve.

 

[lxdude]

Four farthings to a penny

How many nearthings?

 

[glbeas]

Yes. Among other applications, General Motors used it on some fasteners in their engines, in the late 1980s. Other fasteners in the same engines were still SAE inch standard; this is true but I will not be surprised if you don't believe it.

Arghh! Yes I've encountered that bit of insanity before.

 

[lxdude]

Gad, yes. I remember an alternator on a Buick being attached with both metric and US fasteners.

 

[Steve Smith]

I read somewhere that in the late 1970s, MG used Whitworth threaded bolts with metric size heads.


Steve.

 

[Steve Smith]

yes, the brits took metric and imperial and created the worst of both morlds, highly confusing yo any driver. tank liters. go for miles,and mesure fuel efficiency in liters /100km.. go figureou the british empire!

My car measures fuel efficiency in miles per gallon on a little display below the speedometer which measures in in miles per hour. (it is French though!).


Steve.

 

[ME Super]

Ha! Eons ago, one of our tasks for practicing the conversion of units, was to convert the speed of light from miles per second, to furlongs per fortnight.

Thanks for the reminder of old times.

I've never quite understood the big deal about using metric or US measurements. For precise work, you grab a measuring device calibrated in the right units. For photography, unless you are focusing by a scale on a lens for close work, does it really matter? Metric infinity is pretty much the same as imperial infinity. It just has that strange Euro look to the colors... ;-)

My favorite obscure measurement for velocity is attoparsecs per microfortnight. An attoparsec per microfortnight works out to be about 4% faster than an inch per second.

 

[Worker 11811]

How about arcseconds per second?

 

[ME Super]

That would work for angular velocity but not linear. On the surface of the Earth, at sea level, an arcsecond is about 100 feet. If you're higher up, an arcsecond will be more; in Death Valley it will be slightly less.

 

[ambaker]

How about arcseconds per second?

1.

 

[removed account4]

andy

i usually don't think in terms of meters and feet
but chains and links.
i think to myself, there are 100 links in a chain, and a chain is 4 poles
and 4 poles is the same as 25 links and 25 links is about .2meters,

so lets say i am looking at something which is not far away,
i say, that is about 5 links. ... and i look my holga
and it has the 3 bodies ... which translates 5 links as 9 feet or 3 meters.

its pretty easy

 

[Leigh B]

Seems to be a pre-war standardisation but it is likely old equipment was still in use during wartime.

Most of the machine tools (mills, lathes, etc) used to make equipment during WWII were made before WWII,
with many being made before the "industrial inch" standard became commonly used.

In fact, many machine tools made before WWII are still in service today, working just fine and still meeting original accuracy specs.
Of course, they were made at a time when we expected machines to last a century or more, not a month or more.

- Leigh

 

[Steve Smith]

True. And as with most machine tools, they are probably set up with separate measuring instruments rather than the machine's own graduated scales.

With non CNC lathes and mills, I have only ever used the machines' scales to get close. I have always used a vernier caliper or micrometer to do the final measurements.


Steve.

 

[Leigh B]

Hi Steve,

All of my traverse-type macines (mills, lathes, etc) have DROs with resolutions of .0001" or .0002". I never rely on the engraved scales.

(I have a full commercial machine shop with all manual machines, no CNC at all.)

- Leigh

 

[Worker 11811]

That would work for angular velocity but not linear. On the surface of the Earth, at sea level, an arcsecond is about 100 feet. If you're higher up, an arcsecond will be more; in Death Valley it will be slightly less.

Right. It does change but it's not arbitrary. If you are measuring over the surface of the earth we assume that it's ≈100 ft, but if measuring in space you have to consider the distance. Since most people would measure over the earth it's not necessary to consider distance.

The neatest thing is that people often use the shorthand term "second" when they refer to arcsecond. Therefore, one might be able to say they traveled at a speed of 0.01467 seconds per second and that would mean the same as 60 miles per hour.

 

[Ross Chambers]

Shillings. Schilling sounds Dutch.

It's easy. Tuppence is obvious (two pence). Four farthings to a penny, twelve pennies to a shilling, twenty shillings to a pound (240 pence). And don't forget the Guinea - worth one pound and one shilling. It was originally a one pound coin but the price of gold went up so the value of the coin had to otherwise it would have been worth more in gold than its face value.


Steve.

12 was always a sensible base for currency, divisible by 2 3 4 and 6.

Guineas were popular in art dealer circles; that extra shilling added up quite nicely for a big sale.

 

[mrred]

I'm buying a camera where all distance is done in meters. Well, schooling here standardized on feet. Any tricks any of you used to retrain you mind to evaluate in meters? I am aware of the conversion 3 feet = .91 meter, just currious if there are any "tricks" or things that help get the mind to convert faster?

Don't convert. Think in meters or think in feet.

 

[benjiboy]

12 was always a sensible base for currency, divisible by 2 3 4 and 6.

Guineas were popular in art dealer circles; that extra shilling added up quite nicely for a big sale.

We got counting in twelve s from the Vikings Ross, and we still buy eggs and many other things in dozens, although a bakers dozen is thirteen.
Before the U.K adopted metric currency many up market shops priced their products in guineas, it was some sort of mark of exclusivity.

 

[E. von Hoegh]

Shillings. Schilling sounds Dutch.

It's easy. Tuppence is obvious (two pence). Four farthings to a penny, twelve pennies to a shilling, twenty shillings to a pound (240 pence). And don't forget the Guinea - worth one pound and one shilling. It was originally a one pound coin but the price of gold went up so the value of the coin had to otherwise it would have been worth more in gold than its face value.


Steve.

Schilling may sound Dutch, but it is Austrian. What about crowns?

 

[Steve Smith]

Not sure of the origin but a Crown was five shillings (or 60 pence). Four Crowns to the pound. There was also a half Crown which was two Shillings and six Pence. In conversation, the Shillings and Pence were not normally spoken so something costing half a Crown might also be described as costing two and six.

And something which confused me for a long time when I was a child was that the sign for a Pound (£) was really 'L' and the sign for Pence was 'D'.

I couldn't work out why the price label marked 4D actually meant four Pence. Even more confusing was the transition period between the old currency and decimal when most things in the shops had two prices. Did the same thing happen in Europe when the Euro was (almost) universally adopted?


Steve.

 

[benjiboy]

Not sure of the origin but a Crown was five shillings (or 60 pence). Four Crowns to the pound. There was also a half Crown which was two Shillings and six Pence. In conversation, the Shillings and Pence were not normally spoken so something costing half a Crown might also be described as costing two and six.

And something which confused me for a long time when I was a child was that the sign for a Pound (£) was really 'L' and the sign for Pence was 'D'.

I couldn't work out why the price label marked 4D actually meant four Pence. Even more confusing was the transition period between the old currency and decimal when most things in the shops had two prices. Did the same thing happen in Europe when the Euro was (almost) universally adopted?


Steve.

I think I can clear that up Steve, the £ sign looks like a capital L because it comes from a denomination of Roman coinage the Libra, and the D a smaller denomination the Denarious, because remamber the Romans occupied Britain for four hundred years.

 

[E. von Hoegh]

I think I can clear that up Steve, the £ sign looks like a capital L because it comes from a denomination of Roman coinage the Libra, and the D a smaller denomination the Denarious, because remamber the Romans occupied Britain for four hundred years.

The Romans gave us 'ounce', from "uncia", as well.

 

[Steve Smith]

I think I can clear that up Steve

Oh yes, I know all that now. I was confused when I was six years old!!


Steve.

 

[Steve Smith]

These metric advocates are terrible. Give them 2.54 centimetres and they'll take 1.61 kilometres.


Steve.

 

[lxdude]

And something which confused me for a long time when I was a child was that the sign for a Pound (£) was really 'L' and the sign for Pence was 'D'.

And we still have nails designated in pennies, like 10d, 6d, etc. Which I think related to weight, as nails don't cost that much!