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September 30th 03, 03:17 PM

On Mon, 29 Sep 2003 23:38:14 -0500 (CDT),
(Richard Harrison) wrote:

Gene Nygaard wrote:
"Look in the textbooks you used, and see if the authors have any
footnotes citing the authority for whatever definition they use.

My Random House American College Dictionary (circa 1950) says:
"kilogram, n. Metric System. a unit of mass and weight, equal to 1000
grams and equivalent to
2.2046 pounds avoirdupois.

For pounds, the same dictionary says:
"Pound. 1. a unit of weight and of mass, varying in different periods
and countries.

Pounds and kilograms are different units for the same things, force and
weight.

Still haven't figured out that your claims that both kilograms and
pounds are names of both a unit of mass and a unit of force is at odds
with what Dave Shrader and Richard Clark have been telling us, have
you?

Of course, kilograms force were also still quite acceptable units in
1950 when your dictionary was written, before the International System
of Units was introduced in 1960.

Rants in this thread are inane. The world gets by just fine using 2.2046
pounds equal 1 kilogram.

In 1950, that's about as good as they could do--more precise
expressions of this equivalence would have required specifying the
location in which the avoirdupois pounds were used.

That changed in 1959, when the national standards laboratories of the
six major countries using English units got together and defined the
pound as 0.45359237 kg.

But people who care about what they are doing also know that this
conversion factor doesn't work for pounds force, which are converted
to newtons rather than to kilograms in the modern metric system.

The question, "Which is heavier - a pound of gold or a pound of
feathers?"

A pound of feathers is heavier than a pound of gold because gold is
measured in troy pounds while feathers are measured in avoirdupois
pounds. Troy pounds have 12 ounces; avoirdupois pounds have 16 ounces. A
troy pound contains 372 grams in the Metric System: an avoirdupois pound
contins 454 grams. Each troy ounce is heavier than an avoirdupois ounce,
says "The Handy Science Answer Book".

You missed the most important difference between troy pounds and
avoirdupois pounds. The troy units of weight are always units of
mass, never units of force. The avoirdupois units of weight were
units of mass from the beginning, but they recently spawned a unit of
force of the same name (a unit that was never well defined before the
20th century, when people first started using a "standard acceleration
of gravity").
Gene Nygaard
http://ourworld.compuserve.com/homepages/Gene_Nygaard/

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