the imperial/metric system

[rhys 0]

worked up?

no.

just puzzled as to how something that is harder could be the same as something that is easy?

"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

[quade 4]

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just puzzled as to how something that is harder could be the same as something that is easy?

Because you confuse the -name- of the thing, with the thing itself.

Distance is absolute, the unit of measurement is arbitrary.

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One

The Tao that can be told is not the eternal Tao.
The name that can be named is not the eternal name.
The nameless is the beginning of heaven and earth.
The named is the mother of ten thousand things.
Ever desireless, one can see the mystery.
Ever desiring, one can see the manifestations.
These two spring from the same source but differ in name;
this appears as darkness.
Darkness within darkness.
The gate to all mystery.

quade -
The World's Most Boring Skydiver

[SkyDekker 1,465]

eventhough both measurement systems are based on assumptions, the metric system is certainly easier to work with. Everything, be it weight or distance is based on units of ten, that is what makes it easy.

The Imperial system is all over the place and requires much more memorizing of units and their inter-relationship.

I don't think either one is superior over the other in design. Metric however is much more superior than Imperial in its ease of use.

[rehmwa 2]

They are both arbitrary systems. Whatever you use all your life is easier - at first. I work in both and have no issues, one problem is in my field we go back and forth, and that's a real pain.

That said, my car gets 50 cubits to the hectare, and that's the way I likes it.

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Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants

[kallend 2,150]

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eventhough both measurement systems are based on assumptions, the metric system is certainly easier to work with. Everything, be it weight or distance is based on units of ten, that is what makes it easy.

The Imperial system is all over the place and requires much more memorizing of units and their inter-relationship.

I don't think either one is superior over the other in design. Metric however is much more superior than Imperial in its ease of use.

SI is superior in design.

physics.nist.gov/cuu/Units/

Once you get beyond the trivial (volume, length, weight, mass) stuff, Imperial becomes almost impossible to deal with.

So who among the supporters of Imperial can tell me how to calculate the magnetic flux density produced by a current flowing in a coil of wire wound around an iron core, using ONLY Imperial units.

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The only sure way to survive a canopy collision is not to have one.

[rehmwa 2]

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Once you get beyond the trivial (volume, length, weight, mass) stuff, Imperial becomes almost impossible to deal with......magnetic flux density produced by a current flowing in a coil of wire wound around an iron core, using ONLY Imperial units.

It's more interesting to reduce gross units to the basics of l/m/t -> length, mass, and time (is there others? fields tend to be in force at distance by volume so that is reducible). (volume and weight are not trivial, but a mix of the base units - v -> l^3, w -> ml/s^2)

What's the unit of gravity or magnetic flux or power or etc - reduced to the base elements (It's funny and some of the more complex units reduce to things like - t^3m^4/l^.5 which have little intuitive sense - but they are all the same regarless of whether the mlt units are metric or imperial)

No one is stopping a person from converting an imperial problem to metric, and then solving the problem and then converting back. But they better keep track of units if they are doing that.

Say what you will, they are both arbitrary. Metric is friendlier, but Imperial is not 'almost impossible' unless you go in with that bias.

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Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants

[kallend 2,150]

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Once you get beyond the trivial (volume, length, weight, mass) stuff, Imperial becomes almost impossible to deal with......magnetic flux density produced by a current flowing in a coil of wire wound around an iron core, using ONLY Imperial units.

It's more interesting to reduce gross units to the basics of l/m/t -> length, mass, and time (is there others? fields tend to be in force at distance by volume so that is reducible). (volume and weight are not trivial, but a mix of the base units - v -> l^3, w -> ml/s^2)

What's the unit of gravity or magnetic flux or power or etc - reduced to the base elements (It's funny and some of the more complex units reduce to things like - t^3m^4/l^.5 which have little intuitive sense - but they are all the same regarless of whether the mlt units are metric or imperial)

No one is stopping a person from converting an imperial problem to metric, and then solving the problem and then converting back. But they better keep track of units if they are doing that.

Say what you will, they are both arbitrary. Metric is friendlier, but Imperial is not 'almost impossible' unless you go in with that bias.

I have the advantage here. I have seen 35 years worth of science and engineering students (undergraduate and graduate) in my solid state electronics classes grappling with some of these problems. Many stubbornly stick with Imperial because that's what they feel comfortable with. So far, not one has gotten a correct answer to a magnetics or solid state problem using Imperial all the way. Those who use SI for the calculations (and convert the answer to Imperial if the problem asks for the answer in Imperial) generally get everything right. So I think "almost impossible" is a fair description.

PS1 Imperial units are currently defined in terms of the corresponding SI unit.

PS2 Imperial can't even figure out what the unit of mass is. Some books use the slug, and others the pound. If the pound is the mass unit then the poundal is the unit of force. Anyhow, either way we end up with an inconsistency in pressure or stress in conventional psi, in that the force unit requires feet in it's definition, whereas the area unit uses inches., etc etc etc., what a f&^ked up system.

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The only sure way to survive a canopy collision is not to have one.

[rehmwa 2]

as I said, you have to keep your units in line regardless of which system you work in - unfortunately, I have only about 20 years of science and engineering practice, so you'll have to bear with me.

Inability to do correct work due to misapplication of your base unit system is no excuse for the wrong answer. If "not a single student" got an answer right, then I blame the educator, not the measurement system. Sorry, the only common factor is the teacher. Unless you can show that the measurement system is flawed, not just unwieldy.

I also have had professors (a long time ago) with a bias against SI, not only provide little or no help in solving problems presented that way, but also go out of the way to make them difficult (same thing, providing dimensions in feet and pressure in psi, mass for one in lbm and mass for another in slugs, etc). In my mind, their efforts to 'make a point' were nothing better than focused sabotage of the learning process. I mean they never, ever gave the content a mix of kilograms and grams, it was always kg. But it did help spread the curve out for easy resolution.

Again, you id your base units you want to work in, convert all the metrics provided to those units, then work the problem to the answer - then convert the final to the expected units of the bias of your audience. Default metrics for magnetics, etc, you need to understand how the base units define that metric so you can then convert correctly - regardless. (cube root of time/length squared/mass cubed, etc.)

(for the following, if I'm messing up my unit definitions, then my apologies - I'm in a rush)

I mean, what is a "Watt" - it's a power term, that's simply force x velocity - that's really mass x acc x vel - that's really mass x length / time / time / x length / time - or ml^2/t^3

It's still power whether in newton meters second or in inch-pounds per second or in lbforce cubits / day

If the instructor wants Watts - then convert the final result recognizing that Watts requires base units of kilograms, meters, and seconds in some power relation. If you are trying to get a grade, then you are stuck with the prof's prejudices and then do it his way.

Metric systems are not messed up, just the application of those using them. Most of your students likely were off by a factoring constant or three if they understood how to solve problems.

Personally, I'd prefer the whole world standardize to one system, just so we all speak the same language, but I don't have that ability so I work with what's given to me. If it was my choice, I'd say metric. It's less mucked up from it's evolution than the other.

If the student understands the theory, then the canned equations in the text books won't throw them off. Well, maybe the lazier ones...

Edit: even in metric, the higher order 'metrics' have the mass subunit default as the KILOgram instead of the gram, yet not use KILOseconds, or Kilometers. That's also inconsistent. In the words of an intelligent man "What a f*^&cked up system".

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Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants

[kallend 2,150]

I repeat my question to you. What is the Imperial unit of magnetic induction? Of luminous intensity? Of inductance? You may not use any SI units in your answer.

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The only sure way to survive a canopy collision is not to have one.

[wmw999 2,589]

Give me imperial or give me death
I actually found it by doing a search on "slugs shuttle" because, well, the space shuttle software is all done in imperial units.
Wendy W.

There is nothing more dangerous than breaking a basic safety rule and getting away with it. It removes fear of the consequences and builds false confidence. (tbrown)

[rehmwa 2]

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I repeat my question to you. What is the Imperial unit of magnetic induction? Of luminous intensity? Of inductance? You may not use any SI units in your answer.

Actually you didn't ask any question before. So you can't repeat it. Even then, your question is just a semantics game - that's more BillVon's style.

Here's an exercise for you instead to answer your question - break down your unit of inductance into it's base definition consisting of kg, m, and s (anyone familiar with physics and flight should know the power of dimensional analysis - it's where the aerodynamic equations originated). Then replace kg with slug, m with ft, and s with sec. Name it the "Kallend" There you have your Imp unit equivalent and likely will get a research grant for your efforts.

Unless you want to tell me that imperial units don't have a mass, length or time unit (in fact, they have several which is the problem with imp units).

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Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants

[kelpdiver 2]

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eventhough both measurement systems are based on assumptions, the metric system is certainly easier to work with. Everything, be it weight or distance is based on units of ten, that is what makes it easy.

Time is still a mess of 60/12/24. Mph or kmph - still is useless unless you memorize constants like 55mph = 88fps. I already mentioned the fuel economy problem too.

So the latest proof of the superiority of SI is calculated magnetic flux. You're still missing the point of this subject. The needs of the physics community is not going to convince anyone else to change. What DZ is going to foolishly advertize a 4000m exit altitude instead of 13,500ft?

[Andrewwhyte 1]

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Give me imperial or give me death
I actually found it by doing a search on "slugs shuttle" because, well, the space shuttle software is all done in imperial units.
Wendy W.

How quaint.

[billvon 3,120]

>What DZ is going to foolishly advertize a 4000m exit altitude instead of 13,500ft?

Most of them outside the US. Most of the world uses meters instead of feet.

[rehmwa 2]

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>What DZ is going to foolishly advertize a 4000m exit altitude instead of 13,500ft?

Most of them outside the US. Most of the world uses meters instead of feet.

In an international economy, most of the world also uses both. Metric is the default for most of the world.

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Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants

[Casurf1978 0]

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I say, lets all just switch to the metric system once & for all & be done with it. I am 175 cm and 69 kg, and I can deal with that.

I agree. The SI system is much more elegant and easier to use than the English system. Hell how many different types of area units are there in the English system. Example:

"Area: square inch, square foot, square yard, acre, square mile, township, square fathom, square rod, square furlong, square league, square mile"

"volume: gallon, liquid quart, dry quart, liquid pint, dry pint, fluid ounce, teaspoon, tablespoon, minim, fluid dram, gill, peck, bushel, cubic inch, cubic foot, cubic yard."

Damn. Try to figure out how many gallons are in a liquid quart.

The SI is so much easier. All you have to remember is the following: micro, milli, centi, deci, deca, hecto, kilo, mega. How hard can that be.

[jimbarry 0]

kelpdiver said a meter is based on 1/10mill of the earth's circumference. i said it's actually based on 1/10mill the distance between a pole and the equator. i used a winky. he made a little mistake, so what, big deal.

He didn't say "precisely" so neither did I. Nor did either of us intend that this was an exact measurement. This is a forum for skydivers, I was trying to keep geodesy out of it.

And you have yet to provide a source which says the meter is based on the circumference of the earth, which is all I was saying.

As for the rest of your attitude berating me, well, I'll just set that aside, because I prefer rational discourse.

(ed. to make my reply shorter, get to the point)

[kelpdiver 2]

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>What DZ is going to foolishly advertize a 4000m exit altitude instead of 13,500ft?

Most of them outside the US. Most of the world uses meters instead of feet.

Find me one in the US, Bill. Your failure to follow context gets less amusing each time.

I'm still waiting for a real example of how switching to metric would improve Americans's lives. We're happy with our arbitrary constructs.

[mikkey 0]

Here in Australia they switched to the metric system in 70's (AFAIK).
The funny thing is that while people use meters and KG's nearly for everything in day to day live, they use imperial when they talk about a persons height (and to a lesser degree a persons weight (stones)). Altitude (e.g. in aviation or to descibe the height of a mountain) is also always referred to in feet.

On a side note, I remember growing up in Europe and finding the British monetary system very frustrating. Never got a handle on the damn shillings.

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When people look like ants - pull. When ants look like people - pray.

[billvon 3,120]

>I'm still waiting for a real example of how switching to metric
>would improve Americans's lives.

We would have one less thing to bicker about, and we would now know a lot more about Mars.

[Kris 0]

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We would have one less thing to bicker about, and we would now know a lot more about Mars.

ROFL....nice one there about Mars, Bill.

Personally, I'm a born & raised citizen of the USA and I find metric much easier to work with.

Sky, Muff Bro, Rodriguez Bro, and
Bastion of Purity and Innocence!™

[Andrewwhyte 1]

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We would have one less thing to bicker about, and we would now know a lot more about Mars.

[jimbarry 0]

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Worked up? Heck no! For me it's just one of those things that people -think- they know, but in fact don't. Makes for a GREAT bar bet against engineers and, it appears, cartographers. (of all people!)

I accept your bar bet. Go ahead and propose a wager. I'll take the meter based on 1/10mill distance between pole and equator, and you take the meter based on 1/10mill the earth's circumference.

Should be fine by you. You're the one that said I was wrong on that exact same question, right?

As for all of your "precisely" whatever. Well, duh! That's the part you added, and I never said. (Nice debate technique by the way.) Of course the metric system is as arbitrary as any other. Some find it easier to use. Show me where I ever said otherwise.

[kelpdiver 2]

You probably shouldn't criticize his debate tactics when you do the same. He never said it was the circumference.

[sundevil777 102]

Pizzas in Canada are still described in inches (diameter).

The same is true of TV and monitor sizes.

Tires/wheel sizes (diameter only) are still listed as inches.

Don't give in to metric!

People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am