KM vs Miles

[katiewlx]

There aren't any conversions less complicated than multiplying or dividing by 10, and in the metric system, other conversions have been kept to a minimum. It's not often that you're called upon to use conversions like Boltzmann's constant for example.

I often used Katies constant in my higher maths work, got a commendation once for using it and explaining why Id chosen it to the teacher as a solution to a problem

but so explain why multiplying or dividing by 10 is easier than 12 ? youve simply been taught its easier, yet theyre just numbers theres nothing intrinsically different between a 10 or a 12 as a number, base 10, base12, base 16 is no different really other than scalar, that makes it any harder or easier to calculate multiples or divide by it,its simply the pathways you create in memory to do it instantly.

When I was at school, which I know makes me sound terribly old and yes I did attend a school with desks that had inkwells...we were taught the times tables almost by rote to the point the teacher could randomly pick any two numbers from the multiplication tables between 1 and 12,and then pick on you and expect you to give an answer immediately, not calculate it using mental arithmetic, simply respond with the correct answer straight-away.

once you have those numeric pathways forged in your own memory map, dealing with imperial measurements is actually just as much a doddle as metric, and its why they used to teach you numeracy like you that, because you then dont think about the numbers or the complexity of why multiples of 12 are slightly bigger than 10, the answers are just formed automatically.

 

[Tenkaykev]

I think you can cycle alongside part of Salisbury race course. If you would like me to check it out it’s only 3 or 4 miles from my house.

That's very generous of you. It's still a couple of years away so I'll not tempt fate 😉

 

[Alex321]

When I was at school, which I know makes me sound terribly old and yes I did attend a school with desks that had inkwells...we were taught the times tables almost by rote to the point the teacher could randomly pick any two numbers from the multiplication tables between 1 and 12,and then pick on you and expect you to give an answer immediately, not calculate it using mental arithmetic, simply respond with the correct answer straight-away.

once you have those numeric pathways forged in your own memory map, dealing with imperial measurements is actually just as much a doddle as metric, and its why they used to teach you numeracy like you that, because you then dont think about the numbers or the complexity of why multiples of 12 are slightly bigger than 10, the answers are just formed automatically.

I also learned my times tables by rote, and can still automatically give you the answer for anything up to 12x12.
But that is part of the point - we needed to learn them by rote, they weren't automatic.

Because our general numbering system is base 10, everything involving decimal numbers for units is automatic, we only need to think about how many zeros are involved. The 10 times table is one you don't need to memorise by rote, because it is just add a zero to the number.

If we normally had 6 fingers per hand instead of five, our general numbering system would probably have been base 12 - and that would in fact have been a lot better for many things.

 

[YMFB]

That's very generous of you. It's still a couple of years away so I'll not tempt fate 😉

If I get chance I will ride round that way anyway as I think its part of the drove that runs from Harnham to near Shaftesbury. It’s a long time since I rode it so this is a good an excuse as any.

 

[Tenkaykev]

I also learned my times tables by rote, and can still automatically give you the answer for anything up to 12x12.
But that is part of the point - we needed to learn them by rote, they weren't automatic.

Because our general numbering system is base 10, everything involving decimal numbers for units is automatic, we only need to think about how many zeros are involved. The 10 times table is one you don't need to memorise by rote, because it is just add a zero to the number.

If we normally had 6 fingers per hand instead of five, our general numbering system would probably have been base 12 - and that would in fact have been a lot better for many things.

Son worked at one of the big London Casinos. There was a rigid training / selection program which involved aptitude with numbers which iirc involved times tables going way up past 12. There was also a set way to split various combinations of chips and various other procedures. He eventually became a supervisor, keeping an eye on various tables and dropping in when required.

 

[Dogtrousers]

Very early on in my career in 1983 I worked at a big credit card company and for various reasons I, a raw kid, ended up doing some work directly for the financial controller. He was an interesting old-school guy whose party trick was instantly calculating percentages of sums expressed in £Sd in his head. He must have been bereft when decimalisation rendered that skill useless.

He didn't trust these new fangled computers. I only gained his respect when he saw me soldering a cable. Soldering iron = proper skill.

 

[Tenkaykev]

Very early on in my career in 1983 I worked at a big credit card company and for various reasons I, a raw kid, ended up doing some work directly for the financial controller. He was an interesting old-school guy whose party trick was instantly calculating percentages of sums expressed in £Sd in his head. He must have been bereft when decimalisation rendered that skill useless.

He didn't trust these new fangled computers. I only gained his respect when he saw me soldering a cable. Soldering iron = proper skill.

I have a 5v USB powered soldering iron. It's got a very fine tip. When working I had one that had a 2" diameter head that tapered to a chisel tip. It took forever to get up to temperature and on occasion I would give it a helping hand using a propane blow torch 😁

 

[Andy in Germany]

I often used Katies constant in my higher maths work, got a commendation once for using it and explaining why Id chosen it to the teacher as a solution to a problem

but so explain why multiplying or dividing by 10 is easier than 12 ? youve simply been taught its easier, yet theyre just numbers theres nothing intrinsically different between a 10 or a 12 as a number, base 10, base12, base 16 is no different really other than scalar, that makes it any harder or easier to calculate multiples or divide by it,its simply the pathways you create in memory to do it instantly.

When I was at school, which I know makes me sound terribly old and yes I did attend a school with desks that had inkwells...we were taught the times tables almost by rote to the point the teacher could randomly pick any two numbers from the multiplication tables between 1 and 12,and then pick on you and expect you to give an answer immediately, not calculate it using mental arithmetic, simply respond with the correct answer straight-away.

once you have those numeric pathways forged in your own memory map, dealing with imperial measurements is actually just as much a doddle as metric, and its why they used to teach you numeracy like you that, because you then dont think about the numbers or the complexity of why multiples of 12 are slightly bigger than 10, the answers are just formed automatically.

That relies on your brain handling all that sort of thing. Mine simply won't: we had the same multiplication tables, and the teacher would do the same trick of picking people at random, only to be confronted by a silence and a shrug when she asked me.

I still can't remember most times tables apart from 2 and 10. I've developed all kinds of workarounds involving visually seeing the numbers in my head, working from the few I can remember (7x7 is 49 so 8 x 7 is 59 minus three) and things like 9 times tables, where eight nines will be 70 something and the digits will add up to nine so it's probably 72, but next time I'm asked I'll have to do it all over again. This is why metric is easier for me: with imperial measurements even a calculator is only of limited use...

 

[Profpointy]

Metric is a fantasy system, made up by the French in their Revolutionary fervour. What few realise is that they initially got their sums wrong, and didn’t ‘fess up for years for fear of looking like prat’s - as if.
Imperial is a perfectly logical, scientific system, based on observation and testing.

What is the favoured imperial unit of force ?

Follow up question, what is the conversion factor to work out the acceleration of a mass of 1 pound by 1 foot per second?

If you have a sensible answer to the above, why is pressure in pounds per square inch.

Alternatively if the unit of mass is a slug and pounds are exclusively force, why aren't we using slugs to measure mass ?

And for the next stage what are the units of
potential difference and electric current?

The point of all this is that the SI system is a proper system, where a joule of mechanical energy Newton x metre also ties in nicely with volts and amps. With imperial, each unit is fine in and of itself but nothing ties together for different kinds of things

In fairness science is just as bad as astronomers use parsecs, solar masses and such, and nuclear physicists use electron volts for energy and mass and so on

 

[YMFB]

What is the favoured imperial unit of force ?

Follow up question, what is the conversion factor to work out the acceleration of a mass of 1 pound by 1 foot per second?

If you have a sensible answer to the above, why is pressure in pounds per square inch.

Alternatively if the unit of mass is a slug and pounds are exclusively force, why aren't we using slugs to measure mass ?

And for the next stage what are the units of
potential difference and electric current?

The point of all this is that the SI system is a proper system, where a joule of mechanical energy Newton x metre also ties in nicely with volts and amps. With imperial, each unit is fine in and of itself but nothing ties together for different kinds of things

In fairness science is just as bad as astronomers use parsecs, solar masses and such, and nuclear physicists use electron volts for energy and mass and so on

IIRC Pounds Inches

 

[Profpointy]

IIRC Pounds Inches

so your mass unit is slugs then?

 

[Ming the Merciless]

What is the favoured imperial unit of force ?

Follow up question, what is the conversion factor to work out the acceleration of a mass of 1 pound by 1 foot per second?

Unit of force is lbf = 1 lb x g
g ~ 32.174 ft/s^2
To convert to 1lb accelerated at ft /s^2 you simply divide by 32.174 ~ multiply by 0.0311 to give 0.0311 lbf. Round as per degree of accuracy you want. You could for instance just multiply by 3%.

 

[Hover Fly]

I’m given to understand French market stalls sell by the ‘livre’, German stalls by the ‘pfund’.

Back when I worked in a French vineyard, I had a tape measure marked in Pied, or feet, 1 French foot was slightly longer than one of ours, at about 325mm*, a metre was reckoned to be slightly too long to set vines apart in most cases, so trois Pied de Roi it was. It was possible to go into a farmers’ supply and buy one.

Which would be pretty big for a modern man’s foot, so the Louis’ feet must have been huge.

 

[YMFB]

so your mass unit is slugs then?

I don’t remember slugs

 

[Dogtrousers]

I don’t remember slugs

Slugs were invented in the 19th century when users of imperial units looked enviously at SI (or whatever the metric system was called at the time). They saw that a mass of 1kg when subject to a force of 1N accelerates at 1m per second per second.

"We'll have some of that" they said, and invented the slug. They decided that a pound was a unit of force, not mass. A slug is a mass that accelerates at one foot per second per second when subject to a force of 1lbf.

This radical simplification of the imperial system was an immediate hit and everyone adopted it. Not

Meanwhile some other imperial users, decided that a the pound was in fact a unit of mass, not force. They too looked enviously at the metric system and declared that the unit of force was to be the poundal, which is the force that, when applied to a mass of 1lb results in an acceleration of one foot per second per second. Like the slug, with which it is completely incompatible, the poundal was also an immediate hit, and together they simplify things completely