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METRIC ! 52
- Thread starter ceesjan
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- #42
Well, I'll offer this much. I'm only 6 years out of college and I'm much more comfortable with English units that metric. English units are based on "real" things where metric seems to be pretty arbitrary. I can walk down a line and get a pretty good estimate of how many feet I'm dealing with. I can't do that with meters.
I can see where students would have an easier grasp of metric in college, after all, those are all arbitrary problems and a student w/o experience doesn't really have a feel for what the numbers mean. Is 20,000 lbs/in a lot? Is 1 kilopascal a lot? I know those answers now, but 10 years ago, they were just numbers.
And, I doubt that the US government adopted metric at any time, much less 100 years ago. If that were the case, all the road signs, particularly on the interstate highway system, would have had kilomter markers instead of mile markes. Edward L. Klein
Pipe Stress Engineer
Houston, Texas
All opinions expressed here are my own and not my company's.
I can see where students would have an easier grasp of metric in college, after all, those are all arbitrary problems and a student w/o experience doesn't really have a feel for what the numbers mean. Is 20,000 lbs/in a lot? Is 1 kilopascal a lot? I know those answers now, but 10 years ago, they were just numbers.
And, I doubt that the US government adopted metric at any time, much less 100 years ago. If that were the case, all the road signs, particularly on the interstate highway system, would have had kilomter markers instead of mile markes. Edward L. Klein
Pipe Stress Engineer
Houston, Texas
All opinions expressed here are my own and not my company's.
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- #43
RITelectric
Electrical
In truth, practicality and feasibility will determine our future course with this matter, as they should. There will not be a need to switch the U.S. to metric until it can be incontrovertibly shown that the benefits of such a change will outweigh the costs (nickels per slug?).
Speaking of which, there's another discrepency between nations that hasn't yet been resolved, and I contend that it's because the discrepency doesn't need to be resolved: we have different money all over the world, yet we transact international business with nary a glitch, because everyone is used to accomodating for the differences in monetary value between nations.
I say the people who are worried about conducting business with the U.S. have as much valid need for concern about measurements as they do about being over/underpaid for goods and services exchanged.
Seeing as how many different nations do business in the world today, and that there is a different exhange rate between every two that use different currency, AND that those rates change over time, it seems trivial to me that the static set of conversions between English and SI is such a burden. Let those who work with their own units continue to work with their own units, in the interest of pursuit of quality (which is, I think everyone will agree, the fundamental purpose of engineering).
This brings be back to my initial point: Where the world stands today, there will be no crucial benefit to either party if the United States switches to metric. If the rest of the interested world is willing to risk poorer product from the U.S. until it finishes the potentially lengthy adjustment, then go ahead and pursue the change... but there are enough level-headed people in the U.S. to realize it is not a worthwhile task, and I wouldn't expect much more adjustment than has already been made.
The solution to this problem, in my mind, is to overcome the perception of a problem.
If someone needs a unit converted, then convert it. It is far simpler than abandoning a perfectly good system for those accustomed to using it.
Speaking of which, there's another discrepency between nations that hasn't yet been resolved, and I contend that it's because the discrepency doesn't need to be resolved: we have different money all over the world, yet we transact international business with nary a glitch, because everyone is used to accomodating for the differences in monetary value between nations.
I say the people who are worried about conducting business with the U.S. have as much valid need for concern about measurements as they do about being over/underpaid for goods and services exchanged.
Seeing as how many different nations do business in the world today, and that there is a different exhange rate between every two that use different currency, AND that those rates change over time, it seems trivial to me that the static set of conversions between English and SI is such a burden. Let those who work with their own units continue to work with their own units, in the interest of pursuit of quality (which is, I think everyone will agree, the fundamental purpose of engineering).
This brings be back to my initial point: Where the world stands today, there will be no crucial benefit to either party if the United States switches to metric. If the rest of the interested world is willing to risk poorer product from the U.S. until it finishes the potentially lengthy adjustment, then go ahead and pursue the change... but there are enough level-headed people in the U.S. to realize it is not a worthwhile task, and I wouldn't expect much more adjustment than has already been made.
The solution to this problem, in my mind, is to overcome the perception of a problem.
If someone needs a unit converted, then convert it. It is far simpler than abandoning a perfectly good system for those accustomed to using it.
Stressguy
My mistake, it was 1975. Check out the link below
My mistake, it was 1975. Check out the link below
RITelectric
Electrical
Another thought about the last sentence of my previous thread:
If an engineer was presented with two possible solutions to a problem, one complicated and one simple, and there was no solid proof that one solution was more complete than the other... which would he choose to implement if he was a good engineer?
If an engineer was presented with two possible solutions to a problem, one complicated and one simple, and there was no solid proof that one solution was more complete than the other... which would he choose to implement if he was a good engineer?
Thanks for the link, doc11. Still, when they start changing the road signs to be in kilometers for distances and kph for speed, then I'll believe that the government is serious about metric. Even when they do, I'll still be having to make the conversions to figure out how fast I'm driving and how far I've got to drive.
If this USMA wants to get serious about bringing metric to America, they're going to have to do it through the media. Never once have I seen a weatherman on any TV station give out the weather data in anything by English units. If the news stations were to start using dual units in their reporting, with say, the next three years listing English/Metric and then switching to Metric/English, in about 10 years, you might have enough public awareness to put the English units away. Edward L. Klein
Pipe Stress Engineer
Houston, Texas
All opinions expressed here are my own and not my company's.
If this USMA wants to get serious about bringing metric to America, they're going to have to do it through the media. Never once have I seen a weatherman on any TV station give out the weather data in anything by English units. If the news stations were to start using dual units in their reporting, with say, the next three years listing English/Metric and then switching to Metric/English, in about 10 years, you might have enough public awareness to put the English units away. Edward L. Klein
Pipe Stress Engineer
Houston, Texas
All opinions expressed here are my own and not my company's.
Plant experience has shown that the dual units approach does not work. You need to switch cold turkey and plan on losing a generation along the way. The good news is that most old people will just drive faster when they see that the speed limit has been raised to 100. This benefit tends to offset the fact that they no longer no how to buy food or tell the temperature.
I always thought that the imperial system was a better system especially when using units to the base 12 (inches and pound[currency]). It was easy to divide things between people for barter for instance (1x12, 2x6, 3x4)... but now we have grown beyond that using mathematics as a tool for many aspects of life.
We have adopted a base 10 for our counting so it is logical to adopt a base 10 for our units (including money). If we had a choice I would vote for a number system either binary or doudecimal (12) and from that would evolve the units. But what advantage would that give in the conversion...it would never happen. Just like the campaign to have 13 months in a year (each month with 28 days... each month starting on Sunday ..your birthday always on the same day of the week)....It will NEVER happen.
We are stuck with decimal so currency and units should be base 10. By the way I come from Australia where we have been through decimialisation in both currency and units in my lifetime. Onwards to the next big step... which side of the road should we drive or how to divide a circle... 360, 400, radians, 100 or?.
Escher
We have adopted a base 10 for our counting so it is logical to adopt a base 10 for our units (including money). If we had a choice I would vote for a number system either binary or doudecimal (12) and from that would evolve the units. But what advantage would that give in the conversion...it would never happen. Just like the campaign to have 13 months in a year (each month with 28 days... each month starting on Sunday ..your birthday always on the same day of the week)....It will NEVER happen.
We are stuck with decimal so currency and units should be base 10. By the way I come from Australia where we have been through decimialisation in both currency and units in my lifetime. Onwards to the next big step... which side of the road should we drive or how to divide a circle... 360, 400, radians, 100 or?.
Escher
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- #49
Engineers are Scientists.
We should use SI units for our work and be fluent in them.
We should also be able to speak to who we have to, and be able to explain what we want to whomever we want.
Which we should also learn to speak 2 or 3 languages other than our native language.
We should be able to solve any problem given any units.
SI units should be our preferred system and the one we encourage our children to learn and the system for all government projects and those projects who combine the talents of members from multiple nations. It is the only thing that makes sense.
If we are waiting for someone to lead us...who do think it is going to be?
We are the leaders!
We should use SI units for our work and be fluent in them.
We should also be able to speak to who we have to, and be able to explain what we want to whomever we want.
Which we should also learn to speak 2 or 3 languages other than our native language.
We should be able to solve any problem given any units.
SI units should be our preferred system and the one we encourage our children to learn and the system for all government projects and those projects who combine the talents of members from multiple nations. It is the only thing that makes sense.
If we are waiting for someone to lead us...who do think it is going to be?
We are the leaders!
Owg - We have split up the circle into 360 degrees basically since the Sumerians adopted a base 60 and as surveyors we split up the degrees by further 60 subdivisions (minutes) and again (seconds). We repeat this in organizing time (seconds and minutes again). So there could be an argument for base 60.
Which way to face the rockets? Well I hear that many military use the grads (400 to a circle) which is all a foreign language to me.
Which way to face the rockets? Well I hear that many military use the grads (400 to a circle) which is all a foreign language to me.
Escher,
Get familiar with gradients, radians, degrees, minutes, seconds, vectors. As an engineer, you are responsible to know these things. All it would take is 1/2 a day with a good book - now what's so hard about that?
You may argue, "my expertise is Structural".
Because that is true does not negate one's responsibility to the profession to at least be casually familiar with units used in other genre of the same profession.
Come on, we are engineers, we are supposed to be smart, let's at least start acting like it.
Get familiar with gradients, radians, degrees, minutes, seconds, vectors. As an engineer, you are responsible to know these things. All it would take is 1/2 a day with a good book - now what's so hard about that?
You may argue, "my expertise is Structural".
Because that is true does not negate one's responsibility to the profession to at least be casually familiar with units used in other genre of the same profession.
Come on, we are engineers, we are supposed to be smart, let's at least start acting like it.
Massey,
Engineers are not scientists. Scientists do research w/o care or consideration for what to do with the knowledge. Engineers use that knowledge to create useful stuff and solve problems. I would resent being called a scientist.
An engineer who says he can solve any problem is lying, or dilusional and should not be trusted.
And, why is it that we must all get behind this universal language of SI units, yet we must all learn other languages to speak. If we're all supposed to line up behind SI, why not a universal spoken/written language as well?
I must confess, your two posts in this thread look like some pretty odd ramblings to my eye.
Edward L. Klein
Pipe Stress Engineer
Houston, Texas
All opinions expressed here are my own and not my company's.
Engineers are not scientists. Scientists do research w/o care or consideration for what to do with the knowledge. Engineers use that knowledge to create useful stuff and solve problems. I would resent being called a scientist.
An engineer who says he can solve any problem is lying, or dilusional and should not be trusted.
And, why is it that we must all get behind this universal language of SI units, yet we must all learn other languages to speak. If we're all supposed to line up behind SI, why not a universal spoken/written language as well?
I must confess, your two posts in this thread look like some pretty odd ramblings to my eye.
Edward L. Klein
Pipe Stress Engineer
Houston, Texas
All opinions expressed here are my own and not my company's.
Where do I sign up for the Esperanto class?
But seriously, we are arguing semantics as to whether or not engineers are scientists. We do applied science. As to the statement that "scientists do research without care or consideration for what to do with the knowledge", I have known many the engineering academic for whom the same could be said. (And conversely the "scientist" who would bristle at the suggestion that this statement applies universally to his field)
I agree with Massey that we should all be casually familiar with all sets of units. I would also expect that anybody with a formal engineering education in Britain or US already is casually familiar.
Brad
But seriously, we are arguing semantics as to whether or not engineers are scientists. We do applied science. As to the statement that "scientists do research without care or consideration for what to do with the knowledge", I have known many the engineering academic for whom the same could be said. (And conversely the "scientist" who would bristle at the suggestion that this statement applies universally to his field)
I agree with Massey that we should all be casually familiar with all sets of units. I would also expect that anybody with a formal engineering education in Britain or US already is casually familiar.
Brad
Massey,
I was rambling about grads (an angular measure) not gradient (a slope akin to the Tan of the angle). It seems all those years at school learning about pennyweights, bushels, rods, guineas & fathings, chains, gram, litres (liters, see I can at least spell another language) reams, quires, US gallons, BTU’s, calories and short ton were all not in vain as my spreadsheet converter cannot handle many of these.
Can anyone out there tell me why there were 100 links in a chain? It seemed like quite a sensible (land) measurement unit to me.
I was rambling about grads (an angular measure) not gradient (a slope akin to the Tan of the angle). It seems all those years at school learning about pennyweights, bushels, rods, guineas & fathings, chains, gram, litres (liters, see I can at least spell another language) reams, quires, US gallons, BTU’s, calories and short ton were all not in vain as my spreadsheet converter cannot handle many of these.
Can anyone out there tell me why there were 100 links in a chain? It seemed like quite a sensible (land) measurement unit to me.
I'm not sure if this answers your question but:
1 mile = 8 furlongs or 1 furlong = 1/8 of a mile
There are 10 chains in a furlong
There are 100 links in a chain
That makes 8000 links to a mile
These are all exact so 1 link = .66 feet exactly.
Compared to most of our other English units of measurement these are pretty easy to remember. It is almost even intuitive.
I know this doesn't directly your question but at least all the numbers are non-fractional which would have been very convenient to use given the time they were invented.
1 mile = 8 furlongs or 1 furlong = 1/8 of a mile
There are 10 chains in a furlong
There are 100 links in a chain
That makes 8000 links to a mile
These are all exact so 1 link = .66 feet exactly.
Compared to most of our other English units of measurement these are pretty easy to remember. It is almost even intuitive.
I know this doesn't directly your question but at least all the numbers are non-fractional which would have been very convenient to use given the time they were invented.
In case you are still wondering about grads:
explains simply that in a 90 degree angle there are 100 grads. 400 grads per circle.
explains simply that in a 90 degree angle there are 100 grads. 400 grads per circle.
Escher - 100 links in a chain appears to be early use of the metric system by surveyors to make the math easier.
Try to think of a contraption to make your life easier; do your survey work faster and with more precision. After all a 6.5' wooden stick is very cumbersome in the countryside. One of these sticks was called a perch, it has also been called a pole or a rood and most recently in the United States, a rod.
The answer came in the form of a metal chain. The first 16.5' chain with one hundred links came about in England around 1620. Shortly thereafter an English inventor and mathematician named Edmund Gunter designed a more useful "chain". Gunter, being number-oriented, devised a system of land measurement around his "chain."
One Perch = 25 links = 16.5 feet.
Four Perches = a chain of 100 links = 66 feet.
80 chains = one English mile = 5280 feet.
10 square chains = one acre = 43, 560 square feet.
This system worked very well in early America with the vast expanses of land to be surveyed. Because of these vast expanses acreage was easy to compute. Just multiply length times width in chains and links (1/100th of a
chain) to obtain the number of square chains. Then move the decimal point to the left one digit for the amount of acres.
Example: 20.68 chains x 40.17 chains = 830.72 sq. chains or 83.072 acres.
100' Engineers Chain
Made by Chesterman - Sheffield, England circa late 1800's
100 open links, 2 rings per link, 1 swivel, 0.16" wire, cast brass handles, not adjustable.
Tally tags at +/- 10, 20, 30, 40 and center on side rings.
Another advantage of Gunter's chain was his system of counting links. A round brass tag was placed at the center 50 link mark . And from each end every 10 links were marked with a brass tag and pointed fingers to match the number of 10 link increments.
Well, you asked.
Try to think of a contraption to make your life easier; do your survey work faster and with more precision. After all a 6.5' wooden stick is very cumbersome in the countryside. One of these sticks was called a perch, it has also been called a pole or a rood and most recently in the United States, a rod.
The answer came in the form of a metal chain. The first 16.5' chain with one hundred links came about in England around 1620. Shortly thereafter an English inventor and mathematician named Edmund Gunter designed a more useful "chain". Gunter, being number-oriented, devised a system of land measurement around his "chain."
One Perch = 25 links = 16.5 feet.
Four Perches = a chain of 100 links = 66 feet.
80 chains = one English mile = 5280 feet.
10 square chains = one acre = 43, 560 square feet.
This system worked very well in early America with the vast expanses of land to be surveyed. Because of these vast expanses acreage was easy to compute. Just multiply length times width in chains and links (1/100th of a
chain) to obtain the number of square chains. Then move the decimal point to the left one digit for the amount of acres.
Example: 20.68 chains x 40.17 chains = 830.72 sq. chains or 83.072 acres.
100' Engineers Chain
Made by Chesterman - Sheffield, England circa late 1800's
100 open links, 2 rings per link, 1 swivel, 0.16" wire, cast brass handles, not adjustable.
Tally tags at +/- 10, 20, 30, 40 and center on side rings.
Another advantage of Gunter's chain was his system of counting links. A round brass tag was placed at the center 50 link mark . And from each end every 10 links were marked with a brass tag and pointed fingers to match the number of 10 link increments.
Well, you asked.
Perhaps we should defer the changing of all US road signs to SI units. At some point in time they will be obsolete since speed limits will be available on board based on GPS. Looking to the side of the road and spotting an occasional road sign is a primitive method of speed control.
In Canada, as part of a concerted effort to run up a massive debt, we converted all our road signs. These road signs will be an interesting feature for tourists to smile at, just like the milestones at the roadside in England. I haven't spotted any meterstones but I will watch out for them. HAZOP at
In Canada, as part of a concerted effort to run up a massive debt, we converted all our road signs. These road signs will be an interesting feature for tourists to smile at, just like the milestones at the roadside in England. I haven't spotted any meterstones but I will watch out for them. HAZOP at
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