I agree with most of your points. I even agree that problems like "how many nanometers in a kilometer" just teach children to hate the metric system.
However, I have to take issue on the decimeter for two reasons: *To understand metric, you have to understand the system of prefixes. Perhaps a third grader doesn't need to understand from yotta- to yocto-, but should understand from micro- to mega-. We have some here who want nothing to do with the "God-forsaken" prefixes centi-, deci-, deka-, and hecto-, but I don't agree. They are defined by the BIPM as part of the SI, and nothing in the SI Brochure says they can't be used. *The decimeter is really quite useful as the liter is 1 dm³. I don't advocate it for measurement, but when a volume must be calculated, I find it much easier to convert millimeters or centimeters to decimeters and multiply out, vs dividing by 10^6 or 10^3 after the fact. So, I use it "all the time" or, at least, frequently. ________________________________ From: "[email protected]" <[email protected]> To: U.S. Metric Association <[email protected]> Sent: Mon, April 8, 2013 2:14:08 PM Subject: [USMA:52631] The U.S. Isn't as Anti-metric as You Think The recent exchange on this list about radiological units raises a bigger point that is often missed in discussions on the metric vs. customary systems with the public. When it comes to most measurements, people are not as wedded to the customary system as they think. Outside of a few common measurements in ordinary life -- the inch, the mile, the pound perhaps -- customary units don't make that much difference to people. If you say that the speed of light is 300,000 k/s or 186,000 mi/s, how many people comprehend either? The measures are used primarily for comparison or for standards. Ask people how many feet there are in a mile. Most don't know. Ask people how many ounces there are in a pound. Most don't know. Most don't know that there is a troy ounce used to measure gold and an avoirdupois ounce to measure everything else. Ask people how many ounces there are in a quart. Most don't know. Most don't even know that the ounce of mass and the ounce of fluid are different. The metric system is a rational system that is easily understood, once people get past the notion of trying to "convert." The quiz show "Are You Smarter than a Fifth Grader?" recently had a third-grade question: "How many decimetres are there in a metre?" This is what puts people off using the metric system. When was the last time that you used a decimetre? Whenever metric measurements have been introduced as a standard, there has been no public outcry. Have you heard of any public outcry to return to measuring pills in grains rather than milligrams? Have you heard of any public outcry to return to measuring wine in fluid ounces rather than millilitres? Do people even know how many fluid ounces there are in a bottle of wine? Do they even care? All this folderol about opposition to metric "conversion" is a red herring. I decided in my daily conversations not to use feet or inches, but metres and centimetres/millimitres. Not once has anyone asked me: how long is that? One of the websites that I founded has used SI metric only for almost twenty years now. The site has nothing to do with science or engineering, but social issues. Most of the readers are from the United States. Not once in twenty years has anyone even commented on the exclusive use of metric. I think that our motto should be: Just do it! Martin Morrison Metric Training & Eductional Columnist USMA's "Metric Today"
