...And not only non-technical people like non-SI metric units such as the
are and hectare. I know an engineer at a rocket motor manufacturer who told
me that he *loves* metric (particularly the MKS [Meter-Kilogram-Second]
system, but *hates* SI because of the gaps of magnitude between approved SI
units. He said that using only SI units for many calculations involved in
rocket motor design and performance analysis often yields unwieldy,
hard-to-relate-to figures that have ridiculously large numbers of zeroes
after the decimal point.
If a pro-metric professional engineer feels that way about SI as opposed to
the MKS metric system, then farmers, gardeners, architects, and civil
engineers will never give up ares and hectares, and why should they?
They're convenient, easy to visualize, easy to use, and easy to compare with
square meters and square kilometers when necessary. -- Jason
----- Original Message -----
From: "Philip S Hall" <[EMAIL PROTECTED]>
To: "U.S. Metric Association" <[email protected]>
Sent: Monday, January 02, 2006 3:11 PM
Subject: [USMA:35540] Re: Happy New Year
The are and hectare fill an awkward gap between the square metre and the
square kilometre. The ratio of the two is 1:10^6 so there is really room
for a unit between them. If the intermediate unit was 10^3 m^2, it would
represent an awkward area - a square with sides of length 10*10^2 m
(approx
31 m). Alternatively it could be defined as a "metric acre" - a strip
100 m
long and 10 m wide. Neither is particularly satisfactory. An awkward
situation all round.
I see a certain logic in these units:
linear
1 dam = 10 m
1 hm = 10 dam
1 km = 10 hm
common factor 10
Area
1 are = 100 m^2
1 ha = 100 are
1 km^2 = 100 ha
common factor 10^2
Volume
1 L = 1000 mL
1 m^3 = 1000 L
common factor 10^3
I'm not suggesting that they should all be retained but it's interesting
to note the underlying pattern
Phil Hall
