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Old September 30th 03, 10:21 PM
Jim Kelley
 
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Gene Nygaard wrote:
It doesn't cost you any more to pay attention.

Repeat to yourself until you understand it: Weight is an AMBIGUOUS
word. IT HAS SEVERAL DIFFERENT MEANINGS.


What cause have I given you to write to me in such a manner?

The one you cite from the Chemical Rubber Company is, of course, one
of those several definitions. If it always meant the same as mass in
physics jargon, I wouldn't have to point out to you that this is an
ambiguous word, would I?


This is the first you've mentioned anything about it being ambiguous.
Until now, you've just been belligerent and accusational about it.

Didn't you read the message you responded to, especially what
immediately followed the sentence you quoted? Didn't you see what
NIST and ASTM have to say about this? Look at it again, and read it
slowly this time


I'm commenting on what you said, Gene. I have no comment on what NIST
had to say.

Thus the SI unit of the quantity weight used in this
sense is the kilogram (kg) and the verb "to weigh" means
"to determine the mass of" or "to have a mass of".

Examples: the child's weight is 23 kg


Learn to evaluate your sources, also. Those sources are more credible
than any CRC Handbook on this subject.


You need to learn how to attribute yours. I didn't write that. :-)

Your definition of weight is not the proper one to use for your body
weight in the doctor's office or the gym.


I don't write definitions. But the ones I have cited are no less
accurate in the doctors office than the physics lab.

You can, of course, choose not to call this quantity "weight." You
can call it mass instead, if you want to.


As I recall, the argument was about whether to call it a mass or a
force.
It's generally accepted that weight is a force. Problems can arise when
someone claims a mass is a force and vice versa.

Furthermore, it is not an acceptable option to misinterpret what they
are saying, and to misapply an inappropriate definition of weight.


It is possible that you are doing some of the misinterpreting.

You could, of course, argue that we should all change to your usage.


Many people already have, obviously.

Reflecting the apparent dichotomy, the CRC defines the pound both ways:
"1. A unit of mass equal in the U.S. to 0.45359237 kg. exactly.
2. Specifically, a unit of measurement of the thrust or force of a
reaction engine representing the weight the engine can move, as an
engine with 100,000 pounds of thrust. 3. The force exerted on a one
pound mass by the standard acceleration of gravity."


That really shouldn't come as any surprise to you, does it, at this
stage of the game?


I believe I had stated the same thing in so many words, earlier.

Interestingly, they also define poundal, pound mass and pound weight.
No mention of pound force. Evidently, that would be redundant. ;-)


Have you figured out yet what those poundals are, and how they are
used?


Were you not able to ascertain that from my earlier post where I
referenced the definition in Halliday and Resnick?

One thing about the CRC Handbook (which edition?) is that they include
stuff put in there over a period of many years, most of it undated.
Those "pounds weight" are an obsolete term for what are now called
pounds force.


So which units of weight do you think we're supposed to use now?

73, Jim AC6XG