Metric?

[Machpoint005]

1 hour ago, mayalld said:

Well, actually consider the cricket square.

If it truly is square, it is 1/10 of an acre.

So each side of the square is exactly how much? I'll give you a clue, it isn't a chain, and there is a square root of ten involved somewhere. How convenient!

The chain/cricket pitch relationship is to do with the distance between the stumps, as any fule kno.

By the way, 'chainage' on road schemes etc is measured in ....

 

 

... metres.

[Murflynn]

Having studied the Use of English and Mathematics to a reasonable level, I am always amazed at the glib way expressions like '2 times more' are used.

if I said one times more it would mean double, so if I say 2 times more it means treble.

but the bloody meedya use 2 times more to mean twice as much, i.e. double.  if that's what they mean why don't they say it?  

[Murflynn]

I will never forget working in Nigeria on a Shell Petroleum base in 1980.  We were building staff houses, and inherited previously used designs by a UK architect which had been in feet and inches, and had been updated by our own design office to show metric units.  These were all rationalised to match the size of available masonry units, e.g. 9" became 225mm, etc.

Then we were told to pass the design to a local architect, to fulfill Shell's commitment to local input.  The architect had never used metric units and promptly changed the designs back into feet and inches without applying any rationality.  So 225mm became 8 7/8", and so on.

Needless to say his drawings were kept available for inspection in the site office and the contractor (Italian) was issued with the metric drawings, under strict orders not to show them to the architect.

[mayalld]

5 minutes ago, Machpoint005 said:

So each side of the square is exactly how much? I'll give you a clue, it isn't a chain, and there is a square root of ten involved somewhere. How convenient!

The chain/cricket pitch relationship is to do with the distance between the stumps, as any fule kno.

By the way, 'chainage' on road schemes etc is measured in ....

 

 

... metres.

Naturally a cricket square, if truly square will be slightly oversized by a couple of yards.

However, that makes an acre even easier to visualise.

An acre is about the size of 9 cricket squares!!!

The railways aren't having any of this metric nonsense. They use REAL imperial chains.

Of course, even the imperial system could be modified to good effect, and use metric multipliers.

You will have heard of mks cgs and SI, let me introduce you to the FFF system of units, a delightfully olde worlde system of units based on the Furlong, Firkin and Fortnight

Beer will henceforth be sold by the centiFirkin (a pleasing unit of measure somewhat larger than the half pint), and it will be reasonable to spend around a milliFortnight appreciating such a measure

The speed limit on the canals will be amended to 100 Furlongs per centifortnight, which sounds altogether faster than 4mph

[Athy]

Damn you, David, you've got me trying to work out in my head how long a thousandth of a fortnight is.

I think I should be taking 33.6 minutes to drink this measure of ale. Am I close? If so, I must learn to drink a little more slowly than is my custom.

[billS]

Relax, you can down it in 20.16 minutes.

[Athy]

24 minutes ago, billS said:

Relax, you can down it in 20.16 minutes.

For this relief much thanks.

I know where I went wrong: I omitted the stage of converting 336 hours into minutes before dividing.

I did pass O level maths but it was a wee bit of a struggle.

[Machpoint005]

1 hour ago, mayalld said:

Beer will henceforth be sold by the centiFirkin (a pleasing unit of measure somewhat larger than the half pint)

Heretic! There are only 72 glasses of beer in a  firkin (if you're lucky).

"An unpleasant measure of beer well short of a pint" (or well short of half a litre, for that matter).

[WotEver]

2 hours ago, Murflynn said:

Having studied the Use of English and Mathematics to a reasonable level, I am always amazed at the glib way expressions like '2 times more' are used.

if I said one times more it would mean double, so if I say 2 times more it means treble.

but the bloody meedya use 2 times more to mean twice as much, i.e. double.  if that's what they mean why don't they say it?  

Worse to my mind, and commonly used, is "six times less". What does that mean? 1/6?  

[mross]

Two times extra might mean thrice, but two times more means twice.  If I have one apple and you have two, then you have two times more apples.  You could argue that the word 'more' is superfluous.  You have two times the number I have.

[1st ade]

3 hours ago, mayalld said:

..., let me introduce you to the FFF system of units, a delightfully olde worlde system of units based on the Furlong, Firkin and Fortnight

Beer will henceforth be sold by the centiFirkin (a pleasing unit of measure somewhat larger than the half pint), and it will be reasonable to spend around a milliFortnight appreciating such a measure

The speed limit on the canals will be amended to 100 Furlongs per centifortnight, which sounds altogether faster than 4mph

That has GOT to be worth a (non metric) Greenie - if not several

[mayalld]

3 hours ago, Machpoint005 said:

Heretic! There are only 72 glasses of beer in a  firkin (if you're lucky).

"An unpleasant measure of beer well short of a pint" (or well short of half a litre, for that matter).

I did propose the centiFirkin as the replacement for the half pint!

Naturally, many of us would prefer the DoubleCentiFirkin if settling in for a session.

[mayalld]

1 hour ago, 1st ade said:

That has GOT to be worth a (non metric) Greenie - if not several

I cannot claim credit for it!

FFF was a creation of the Sheddi back in the old usenet days on uk.rec.sheds

They also came up with Shedspace theory, a warping of space-time by means of which wormholes in shedspace opened up between any sheds that contained enough tqt, and that said tqt was then free to move at random between sheds as needed by the Sheddi.

 

[mayalld]

4 hours ago, Athy said:

Damn you, David, you've got me trying to work out in my head how long a thousandth of a fortnight is.

I think I should be taking 33.6 minutes to drink this measure of ale. Am I close? If so, I must learn to drink a little more slowly than is my custom.

:-)

One of the great things about FFF is that as soon as you explain it, you know several people will have the calculators out to work out what it means.

A millifortnight is slightly over 20 minutes.

The microfortnight is about 1.2 seconds

[Athy]

1 hour ago, mayalld said:

:-)

One of the great things about FFF is that as soon as you explain it, you know several people will have the calculators out to work out what it means.

A millifortnight is slightly over 20 minutes.

The microfortnight is about 1.2 seconds

As you can tell, I did not use a calculator!

[billS]

9 hours ago, Athy said:

As you can tell, I did not use a calculator!

...and the abacus has been out of order since the last abacus repair technician retired in 1987...

[Athy]

4 minutes ago, billS said:

...and the abacus has been out of order since the last abacus repair technician retired in 1987...

No, I used only my brain, parts of which may have been out of order for about the same length of time.

[Captain Pegg]

16 hours ago, mayalld said:

The railways aren't having any of this metric nonsense. They use REAL imperial chains.

Only for referencing physical position of assets. They are not so old fashioned as to design and set out in imperial units although the term "chainage" has morphed into modern surveying.

One of the problems encountered is that as surveying techniques become more accurate things turn out not to be where it was always thought they were.

Use of GPS location is becoming commonplace and that will ultimately metricate the system.

JP

Edited June 13, 2017 by Captain Pegg

[mayalld]

6 minutes ago, Captain Pegg said:

Only for referencing physical position of assets. They are not so old fashioned as to design and set out in imperial units although the term "chainage" has morphed into modern surveying.

One of the problems encountered is that as surveying techniques become more accurate things turn out not to be where it was always thought they were.

Use of GPS location is becoming commonplace and that will ultimately metricate the system.

JP

GPS is metric?

last time I checked, latitude and longitude was an area where we still use degrees minutes and seconds.

Even if you start using degrees and decimal degrees, it still isn't using the SI unit.

[Machpoint005]

10 minutes ago, mayalld said:

GPS is metric?

last time I checked, latitude and longitude was an area where we still use degrees minutes and seconds.

Even if you start using degrees and decimal degrees, it still isn't using the SI unit.

With the planet being an oblate spheroid it would be a bit difficult not to use degrees or radians (which are dimensionless, as you know). I'm not aware that either the imperial or metric systems have a monopoly on those.

 

 

Mach number is dimensionless too...

[mayalld]

2 minutes ago, Machpoint005 said:

With the planet being an oblate spheroid it would be a bit difficult not to use degrees or radians (which are dimensionless, as you know). I'm not aware that either the imperial or metric systems have a monopoly on those.

 

 

Mach number is dimensionless too...

The SI unit of angle is the Radian

If GPS was Metric, it would use Radians

[Machpoint005]

2 minutes ago, mayalld said:

The SI unit of angle is the Radian

If GPS was Metric, it would use Radians

I didn't say SI, I said metric. Not the same thing.

[Captain Pegg]

11 hours ago, mayalld said:

GPS is metric?

last time I checked, latitude and longitude was an area where we still use degrees minutes and seconds.

Even if you start using degrees and decimal degrees, it still isn't using the SI unit.

To the user positional information is given using Cartesian co-ordinates so it is metric. However I guess those co-ordinates are from an origin that can only be defined using longitude and latitude but it is an assumed origin because it uses a planar projection.

In surveying and design of the West Coast Main Line - which has a fixed track position -  a series of planar grids had to be linked into a 'snake grid' that compensated for the curvature of the earth and allowed a continuous calculation of track position from London to Glasgow. The same issues must affect the setting out of long pounds in canals.

Obviously no-one has come up with a better system for measuring angles as the degree seems to have its origin in ancient history, possibly related to days in a year. It may not be an SI unit but they ain't got nowt else.

JP

[mayalld]

15 hours ago, Captain Pegg said:

To the user positional information is given using Cartesian co-ordinates so it is metric. However I guess those co-ordinates are from an origin that can only be defined using longitude and latitude but it is an assumed origin because it uses a planar projection.

In surveying and design of the West Coast Main Line - which has a fixed track position -  a series of planar grids had to be linked into a 'snake grid' that compensated for the curvature of the earth and allowed a continuous calculation of track position from London to Glasgow. The same issues must affect the setting out of long pounds in canals.

Obviously no-one has come up with a better system for measuring angles as the degree seems to have its origin in ancient history, possibly related to days in a year. It may not be an SI unit but they ain't got nowt else.

JP

SI has the Radian.

Why is that not used?

[Scholar Gypsy]

GPS (and now most chart plotters) use WGS84

https://en.wikipedia.org/wiki/World_Geodetic_System

It's an oblate spheroid (squashed sphere) with radius 6378137 m at the equator and 6356752.3142  at the poles. So positions and heights are measured relative to this grid. 

The radian is a SI derived unit. I was actually rather surprised to see it on that list, as it is dimensionless and is independent of whether you measure lengths in metres or furlongs.

 https://en.wikipedia.org/wiki/SI_derived_unit