Dear Bill and All, Readers of "metrication matters' should have no troubles remembering the SI prefixes. I reproduce this item from 'Metrication matters 4'.
Prefix mnemonics Many activities have memory helpers for beginners so that they can readily become involved, and they can develop confidence quickly. Well-known examples are the word F-A-C-E used to remember the 'space' notes of the treble clef stave in music. This is associated with the sentence 'Every Good Boy Deserves Fruit' to remember the 'line' notes E, G, B, D, and F. These memory helpers are technically known as mnemonics, from Greek words associated with mindfulness and remembering. However, I have not found equivalent mnemonics to help young people learn SI basics, such as the names of the prefixes. I have devised two mnemonics to help people learn SI prefixes easily. Details of the development and rationale for these mnemonics is indicated in these tables. Prefixes less than 1 (sub-multiples) millie, mike's nana, pickled fish at zepto's yacht(o) milli micro nano pica femto atto zepto yocto m � n p f a z y 10^-3 10^-6 10^-9 10^-12 10^-15 10^-18 10^-21 10^-24 Note: I considered fems instead of fish, but I couldn't bear its sound or its political incorrectness. Prefixes more than 1 (multiples) killer Meg, Giggling, Terrified Peter's Extra Zits. Yuk! kilo mega giga tera peta exa zetta yotta k M G T P E Z Y 10^3 10^6 10^9 10^12 10^15 10^18 10^21 10^24 Note: I considered 'kindly Meg' but then I grew to like 'killer Meg' much better. I make no apology for the silliness of the words that I chose for these mnemonics. Mnemonics seem to work best if they contain off-the-wall ideas or reasonably strong rhymes or rhythms; I've been wondering for years why: 'Every Good Boy Deserves Fruit'; but the mnemonic still works, and works well. Cheers, Pat Naughtin LCAMS Geelong, Australia Pat Naughtin is the editor of the free online newsletter, 'Metrication matters'. You can subscribe by sending an email containing the words subscribe Metrication matters to [EMAIL PROTECTED] -- on 16/2/04 7:35 AM, Bill Hooper at [EMAIL PROTECTED] wrote: > Gavin wrote: >> Does the current SI >> system (or the old metric system) have a prefix for 1/100,000? > > No, it does not because none is needed. Steps of 1000 between one unit > and the next larger (or smaller) unit are sufficient. > > It is true that steps of ten are used between 1 and 1000 and between > 0.001 and 1 (namely; centi, deci, deka and hecto). These are vestiges > of the early metric system and have not been entirely eradicated from > the current SI. They are still officially acceptable and many people > feel they should be kept. (Others, like I, don't.) > > After the beginning, when a new unit was created for every multiple of > ten, it was quickly realized that such a scheme would lead to too many > units (ie, too many prefixes) and would therefore be difficult and > clumsy. In all newer parts of SI, there are only steps are 1000. As it > is there are 16 SI pefixes (including centi, deci, deka and hecto). Do > you know all 16? (I do!*) But I'm not sure I could (or would want to) > learn 48 prefixes that would be necessary if we wanted one for every > step of 10 up and down the scale. > > > Regards, > Bill Hooper > Fernandina Beach, Florida, USA > > deka 10 > hecto 100 > kilo 1000 (or 10^3) > mega 10^6 > giga 10^9 > terra 10^12 > peta 10^15 > exa 10^18 > zeta 10^21 > yotta 10^24 > > and > > deci 1/10 > centi 1/100 > milli 1/1000 (or 10^-3) > micro 10^-6 > nano 10^-9 > pico 10^-12 > femto 10^-15 > atto 10^-18 > zepto 10^-21 > yocto 10^-24 > > OK, so I'm showing off. I did these from memory, then checked. I found > only one error which I corrected above. I had omitted exa. > > Do you need the symbols? Most of them are just the first one letter of > each prefix, capitals for all those from mega on up, lower case for the > rest. The only exception is the two letter prefix "da" for deka. >
