From: Chris Trayner <C.Trayner@leeds.ac.uk>
To: "rsgb_lf_group@blacksheep.org" <rsgb_lf_group@blacksheep.org>
Date: Fri, 7 Jan 2011 13:15:44 +0000
Thread-Topic: LF: Re: JA GRRABBERS at a same time
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Dear All,

>>> Hertz is a meaningless label in fact its someones Name and is technica=
lly
>>> inapproapriat when describing Frequency.
>>=20

I think the real reason for changing from cycles/second is that the units=
 describe the dimensions of the quantity. Dimensions in physics are relati=
vely few things: mass, length, time etc. Cycles are not a dimension, so a=
 tidying up of the old name would rename it "per second" or "1/seconds",=
 which most would find confusing.

As for the name hertz (named after Heinrich Hertz who didn't discover freq=
uency ...), I suspect much of this was down to bargaining inside whatever=
 committee defined SI. They managed to largely reconcile the warring tribe=
s of CGS and MKS, so I think we have to accept some unfortunate decisions.=
 The old CGS+MKS systems certainly were a major mess, e.g. 1000 calories=
 =3D 1 Calorie.


> Whatever happened to LITRES and JARS?

If you want to keep This Sceptred Isle as the last bastion of eccentric un=
its, note that you could validly descibe voltage gain in fathoms per metre=
. I have a friend who wrote a booklet giving the speed of light in such us=
eful units as furlongs per fortnight*.

73,
Chris G4OKW


* 1.803 x 10^12. But then I expect you knew that.

-----------------------
Dr Chris Trayner
School of Electronic & Electrical Engineering,
The University of Leeds,
Leeds LS2 9JT, United Kingdom
Tel: +44 113 34 32053
Fax: +44 113 34 32032