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SI units

Herb, thanks for the historical insight into the apparent resurrection of
'pico' by the SI system.

I wonder how many other 'new' ideas, terms etc are just reincarnations of
an older form.

For the record, the unit is farad (small letter) and the abbreviation is F
(capital letter). This convention of lower case for the spelled-out unit
and upper case for the single letter abbreviation applies to all SI units
that are named after people and is called the Conservation of Printer's Ink
rule.

The only SI units that are NOT named after people are the second, meter and
kilogram. (I guess this means that the liter and the mol are not truly
correct SI units?)

Question - Why was mmf used instead of pf.
-
Since I am older than Palmer, I will answer.
pico had not been invented yet.

Thought Alex might be amused by this:

Capacitance:..."The farad is too large a unit for
radio or electrical work; hence the microfarad...
and the micromicrofarad...are commonly used."

Picofarad: "Obsolete term for micromicrofarad."

Electronics Dictionary, Cooke & Markus, McGraw-Hill, 1945

Also...in the second edition of the International Dictionary of
Physics and Electronics:

"FARAD. A unit of capacitance, abreviation f or fd. The farad is
the capacitance of a capacitor (or condenser) which acquires
a charge of one coulomb when a steady potential difference of one
volt is maintained across its terminals. the microfarad (10^-6 f) and
the micromicrofarad (pico farad) 10^-12 f) are used as units of
capacitance much more than the farad.

Herb Gottlieb from New York City
(Where people in our streets do not know a farad from a ferret)
(or that the plural of mongoose begins with a 'p'?)

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