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Our Friend, The Meter
dbirchall writes "Upon hearing that SpaceShipOne reached 100km today, I did some hasty math based on the altitude in feet sttated by Scaled Composites in their press release, and was surprised to come up with a number under 100,000 meters. Fortunately, a friend pointed out that my inches-to-meters conversion was flawed. Some quick Googling determined that lots of people still have no idea how many inches are in a meter, even after some folks have had big problems because of conversion errors."
Here in Canada made the switchover... in my lifetime, even.
I had just barely started school when I first heard that that Canada would be moving to the metric system. At the time, there were fewer than 10 countries worldwide that did not yet use the metric system.
Today, the USA alone bears the distinction of being the only nation on the planet that has not yet made any sort of government sponsored effort to switch to the metric system. I find this slightly amusing personally.
The conversion didn't happen overnight in Canada, and in many situations, people still use the imperial measurements. The signage has all been changed, of course... but a lot of people still think in imperial units, so they still get used. I estimate that it will probably take another 40 years before this country really doesn't use imperial units anymore.
Personal anecdote: not that long ago, I was describing something to my kids and mentioned a measurement in yards. My children had no idea how long a "yard" was until I described the length with my hands... to which they said "Oh, you mean a metre!" As the measurement I was citing to them was just an estimate anyways, I told them yes... but I told them that a yard was about 3 and a third inches shorter than a metre. I got another blank stare at the word "inch", at which point I told them there is 36 inches in a yard... Suffice to say I was certainly not winning their approval of my archaic measuring technology.
They just shook their heads and said that the metric system is so much better. Personally, I agree... but it's hard to change what you first learn. That's why I give it another 40 years... there's still too many working class adults that are using the imperial system here.
File under 'M' for 'Manic ranting'
The net result was a backlash that delayed adoption of the metric system here by decades. Instead of the in-your-face road signs, they should have just quietly started converting smaller things over and let the old system fade away gradually.
We probably will eventually switch over, but this won't happen until after our capability to design or manufacture anything domestically has totally atrophied, and we rely on 100% metric imported goods.
READ - Click on posters link
This evening, I learned that one meter equals 39.3700787 inches. While this may come as no surprise to some people, it was one to me - for years, I had mistakenly believed a meter was 39.77 inches, and now I know it's basically 39.37.
Of course, I'm not alone in my confusion. A bit of research on Google revealed quite a few different conversions from meters to inches. Here are some of them:
* 38 inches according to a page at Arkansas State University and another at Microflex Technologies.
* 38.16 inches according to a rounding-happy math teacher at Norfolk Collegiate School in Virginia.
* 38.37 inches according to Honeywell's Sensotec folks.
* 38.8 inches according to some numerological babble
* 39 inches according to Fife Products and some folks who sell quilting products.
* 39.14 inches according to the specifications on a measuring wheel for engineers. (uh-oh!)
* 39.15 inches according to an October 30 2002 entry in a blog.
* 39.21 inches according to Richard Bowles.
* 39.27 inches according to pages at University of Wisconsin Stevens Point and the National Optical Astronomy Observatory.
* 39.28 inches according to Jonathan Brooks at Penn State University.
* 39.3 inches according to some laser folks.
* 39.34 inches according to a page about photography, and another about a role-playing game. Hey, it's only a game, their meters can be whatever length they want.
* 39.36 inches according to some ham radio sorts and some NASA folks among others. Pretty close... but... shouldn't NASA know better by now?
* 39.38 inches according to people who race 1-meter model yachts, talk about prehistory in California, and, um, other NASA folks. Again, pretty close!
* 39.39 inches according to someone ranting against metric (how ironic), as well as a page about UFOs.
* 39.4 inches according to a list of conversions from a company that makes electric motors and such things, and the Secretary of the Navy.
* 39.45 inches according to a set of math problems from a university in the Philippines.
* 39.5 inches according to a space.com article on liquid lenses.
* 39.54 inches according to Mark Moburg in this mailing list archive.
* 39.6 inches according to a page about magnetic therapy.
* 39.7 inches according to pages from Des Moines Area Community College and some rounding-happy laser people.
* 39.77 inches according to a page about carpet-weaving in Turkey and another site that sells S-Video Cables and lots of other cables. (See, I wasn't alone!)
* 39.79 inches according to InterlinkBT (now Turck)'s information on DeviceNet Pre-molded Fieldbus cables (below table).
* 39.87 inches, according to a textfile compiling handy (if wrong) conversions for common weights and measures, from O'Reilly.
* 39.97 inches, according to the Science Glossary developed by teachers in the Poughkeepsie (New York) City School District for the 2001-2002 school year, and according to the zoning laws on satellite dishes in Springfield Township, Ohio.
* 40 inches, according to the U.S. Department of Agriculture.
Once again, the correct answer is right around 39.37 inches. Remember that - it'll be on the quiz!
:wq ~ ~ ~ ~ ~
I couldn't agree more, after all, 2.54 is a really easy number to remember and since I'm an American living in Norway, I find that I still convert a great deal. My coversions are generally based on quick conversions.
For example, if there are 2.2lbs in a kg. Then it's easy enough to use the quick multiply by 11 rule and then multiply by two (or reverse order). So for 52kg it's easy to say that 5 + 2 = 7 so 52*11 = 572 or 52 * 1.1 = 57.2 and 57.2 * 2 = 114.4. So 52kg = 114.4lbs.
As for feet to meters. There are a few quick conversion that aren't of great precision, but accurate enough for day to day life. For example, 3m = 10ft, 1 in. = 2.54cm, 1m = 40in. Of course for precision, I would alway use the 2.54 and a calculator to derive that there are 39.37007874015748031496062992126 inches in a meter. But with the engineering work that I do, it's more typical to simply derive directly the units by converting to and from centimeters and not meters.
As for volume. I of course for quick calculation simply relate the liter to the quart since when it comes to serving drinks, there's not a great deal of difference. When I need precision, it's easy to remember the numbers I've seen on American Coca-Cola bottles my entire life. A 2 liter bottle always says 67.6 fluid ounces on it. This is my base point for conversion since I can deduce that 33.8 fl oz is 1 liter. From there it's all easy.
For temperature, that's a no brainer. 0c is freezing, 100c is boiling. 32F is freezing, 212F is boiling. So 212 - 32 = 180 and 100 - 0 = 100. Therefore it's easy to asume that 180/100 is the ration. That easily converts to 9/5. Compensate for the 32 degree shift on the farenheit side.
After living here for 5.5 years and effectively performing as a calculator for everyone that needs conversions. I can convert the systems with utter ease and simplicity. I have multiple reference points which I can use in order to estimate measures within a 5% margin or error for all human weights and heights. I also can convert distances with ease (after all 60miles = 100km. 100miles = 160km, it's all gravy from there).
So what it boils down to is that if you can get through school in any country without understanding that both systems are just REALLY REALLY simple. Then go back to school and work on it. Let's face it, there's too much stupidity on this planet. If you can remember there's 12 inches in a foot and 8 oz in a cup, then you can remember 3 points of conversion reference and derive the rest.
Oops... almost submitted without adding this to make the stinkin brits happy, first of all, ASE measurement is not imperial although it has much in common. The imperial measure has a different size for the volumetric measure. Instead of 33.8140226 U.S. fl. oz. in the imperial system has 35.1950652 fl. oz. in a liter.
My Dad wrote a gardening book, when NZ went metric they 'translated it to metric' ... converted all the places where he said "plant the seeds an inch apart" to "plant the seeds about 2.54cm apart" .... silly of course and people quickly learned to do the everyday approximations we mostly use for day to day usage. 50mph is the speedlimit because it's a ound number in the right range, so is 80kph. Buying a pound of meat for dinner is about the same as buying 1/2 a kilo - both will get you fed about right. Half a litre is about a pint, a metre is about a yard. A 2x4 is about a 10x20 etc etc ... honestly I don't understand why americans are so scared about changing
I wish. We've had to deal with everything in inches for years from NASA, now our requirements are a mix. They say we need to detect 1/4" damage from 5 to 7 feet moving at up to 1 meter/min and 1" damage from 7 to 10 feet at up to 3 meters/min. To make matters worse, our scanner measures in millimeters, so we have to convert the spec to mm anyway to know that we can meet the spec. And this is a safety-of-flight program to ensure the shuttle is not damaged.