On Wed, 01 Oct 2003 10:32:56 -0700, Jim Kelley
wrote:

Gene Nygaard wrote:
They are incorrect in the doctor's office, and even more incorrect in
the supermarket or the jewelry store. Like I said, you don't have to
call the quantities used there "weight"--but if you do call them
weight, use the definition which is correct in that context. Don't
misinterpret what is being used there.

Do you know what you're talking about Gene? Cuz I sure don't.

It's generally accepted that weight is a force.

I've shown in this thread from the experts in the field, including
NIST (the U.S. national standards agency) and ASTM (an industry
standards agency) and NPL (the U.K. national standards agency) and the
Canadian Standard for Metric Practice, that this is false.

I don't agree.

All of
these sources and many others tell you that weight is an ambiguous
word, with several different meanings.

What physical quantity do you think a grocery store scale measures?

You can probably figure that out for yourself, if you stop to think
about how they are tested and certified.

Especially if you have enough common sense to figure out that when we
buy and sell goods by weight, we wouldn't want to measure some
quantity that varies with location.

Another big clue is the units in which that quantity is measured;
grams in most of the world, and at least on prepackaged goods in the
United States. In that regard, you might also consider how the law
defines a pound (i.e., 0.45359237 kg), and then ask youself why in the
world the law bothers defining a pound in the first place.

When I was a kid, almost all the scales in the grocery stores were
balances. You do understand what Richard Clark, among others, has
told us about what we measure with those balances, don't you? Sure,
they had evolved to the point where you didn't have to place loose,
individual weights on a pan to get them to balance. The store we used
most often had one with a dial readout, and a computing scale listing
total price based on various prices per pound, but it prominently
displayed the company motto on the side facing the customer:

HONEST WEIGHT
NO SPRINGS

That scale wouldn't give you any different reading atop Mt. Chimborazo
or at the North Pole than it did in the store in which it was used.
Now, after the invention of the microprocessor, we have other options
with reasonable cost and performance to accomplish the same thing.

Problems can arise when
someone claims a mass is a force and vice versa.

I agree.

And so a torque wrench has what kind of units printed on its scale -
mass and distance, or force and distance?

Once again, it doesn't cost you any more to pay attention.

Like I told you a long time ago, my torque wrench has "meter
kilograms" on it. What does that tell you? Why didn't you answer me
then?
Message-ID:
Date: Fri, 26 Sep 2003 23:35:11 GMT

Though I have had mine for several years, such torque wrenches, of
course, are still readily available.
http://jcwhitney.com/webapp/wcs/stor...&storeId=10101

They are units of force and distance, if you can't figure it out, just
as the "foot pounds" which are the other units on my wrench are. But
just as the existence of the kilogram force does not prove that pounds
are not units of mass, the existence of pounds force does not prove
that pounds are not units of mass.

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

Many people already have, obviously.

Not very many, surprisingly.

Just the ones who write physics books maybe?

It is much more common to find people
claiming, erroneously, that there is some error in that usage.

You're the first guy I've ever seen making claims about errors in usage.


Like slugs, poundals only exist in one limited purpose system
of mechanical units, mostly used to simplify calculations.

But you'd like us to believe the unit of mass in that system is
ubiquitous and universal, and that everybody is wrong!

The pound, of course, like the foot and the second, predates that
system, and those units are all used in many other systems as well as
outside any such specialized system. IIRC, there is only at most one
unit in any of the commonly used specialized systems of English
mechanical units that was invented specifically for use in that
system: the poundal in the absolute fps system, the slug in the
gravitational fps system, the slinch in the gravitational
inch-pound-second system. The old metric cgs systems have two
mechanical units with special names that aren't in other systems, the
dyne and the erg, and of course they also have various names in the
different flavors of cgs for electrical and magnetic units, quantities
that have never been measured in English units. Of course, you also
have combinations involving those units, such as foot-poundals.

That the poundal system is much older than the slug system is merely
one of the many clues as to which is older, the pound mass or the
pound force.
Gene Nygaard
http://ourworld.compuserve.com/homepages/Gene_Nygaard/

On Wed, 01 Oct 2003 03:42:41 GMT, KU2S wrote:

On Tue, 30 Sep 2003 14:17:53 GMT, Gene Nygaard
wrote:

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?


Okay people.... before this thread goes any further wrong than it
already has....

Kilograms (base unit of measurement, the gram) are units of MASS.
This is a measure of the amount matter in an object...

Pounds are a unit of force, a measurement of the gravitational
attraction a body has relative to another, reference, body.

A 2 kilogram object will have the same mass on the earth as it does on
the moon.

A 60 pound object on the earth will have a weight of 10 pounds on the
moon.

If you kiddies are going to argue physics, you really SHOULD get your
terms straight.

God, pseudo-intellectuals really do begin to wear thin quite
quickly...


Raymond Sirois KU2S

So what about those "meter kilograms" on my torque wrench?

What's a poundal?

Did NIST get it wrong, in what I pointed out in response to Richard
Clark's challenge?
http://physics.nist.gov/Pubs/SP811/appenB8.html#P

To convert from to Multiply by

pound (avoirdupois) (lb) 23 kilogram (kg) 4.535 924 E-01
pound (troy or apothecary) (lb) kilogram (kg) 3.732 417 E-01

[The 23 is a reference to a footnote in the printed and pdf versions,
a note on a separate page in html]
http://physics.nist.gov/Pubs/SP811/footnotes.html#f23

23 The exact conversion factor is 4.535 923 7 E-01. All units
in Sec. B.8 and Sec. B.9 that contain the pound refer to
the avoirdupois pound.

How is the pound officially defined in Canada (Weights and Measures
Act of 1953), in the United Kingdom (Weights and Measures Act of
1963), in South Africa, in New Zealand, in Australia, in Ireland and
in other places as well as the United States, whose definition you can
read at
http://www.ngs.noaa.gov/PUBS_LIB/Fed...doc59-5442.pdf
http://gssp.wva.net/html.common/refine.pdf

But since you are so convinced that this is a "physics" problem, let's
just review the last of the examples I quoted earlier from the
textbook authors recommended by Dave Shrader.
Francis Weston Sears and Mark W. Zemansky, University Physics,
Addison-Wesley, 4th ed., 1970.

[page 232]

The quantity of heat per unit mass that must be
supplied to a material at its melting point to convert
it completely to a liquid at the same temperature is
called the heat of fusion of the material. The quantity
of heat per unit mass that must be supplied to a
material at its boiling point to convert it completely
to a gas a the same temperature is called the heat
of vaporization of the material. Heats of fusion and
vaporization are expressed in calories per gram, or
Btu per pound. Thus the heat of fusion of ice is
about 80 cal g^-1 or 144 Btu lb^-1. The heat of
vaporization of water (at 100°C) is 539 cal g^-1 or
970 Btu lb^-1. Some heats of fusion and
vaporization are listed in Table 16-2.

Now, it doesn't take a whole lot of genius to figure out what the
quantities are which are measured in those units with the -1
exponents, does it?

But you don't even have to guess. Sears and Zemansky come right out
and tell you. For you and some of the other slow-witted folks in this
thread, here's a hint: Look for the seventh word in each of the first
two sentences, that little word sandwiched in between the words "unit"
and "that." Did you find it?

******************

That's as far as I went last time around. But this time we are
dealing with real deep-rooted stoooopid, so I can't leave anything to
the intelligence of the intended reader.

That seventh word which I'm pointing out to you is spelled m-a-s-s.
Do you see it now, Raymond? That's "mass," right?

Now, let's compare the parallels in the construction here. In terms
of the quantities being measured, this is expressed as

quantity of heat per unit of mass

and in terms of the units used to measure these quantities, it is
expressed this way

Btu lb^-1

Now, let's match them up:

o The "quantity of heat" is measured in the units "Btu"

o The "per" corresponds to the superscript -1 (that Btu lb^-1 could
also be written as Btu/lb where the slash would correspond to "per")

o The quantity "mass" is measured in the units "lb"; now that is
the abbreviation, from one of its Latin names, for the units which
Sears and Zemansky call pounds.

Gene Nygaard
http://ourworld.compuserve.com/homepages/Gene_Nygaard/
Gentlemen of the jury, Chicolini here may look like an idiot,
and sound like an idiot, but don't let that fool you: He
really is an idiot.
Groucho Marx

Gene Nygaard wrote:
What physical quantity do you think a grocery store scale measures?

You can probably figure that out for yourself, if you stop to think
about how they are tested and certified.

You misunderstand, Gene. It's not at all clear what _you_ think they
measure. I'm not asking about the units displayed on them. What
physical quantity do you think is actually being measured?

And so a torque wrench has what kind of units printed on its scale -
mass and distance, or force and distance?

Once again, it doesn't cost you any more to pay attention.

They are units of force and distance,

There's the point.

That the poundal system is much older than the slug system is merely
one of the many clues as to which is older, the pound mass or the
pound force.

Ah, older. So that means.........what?

73, Jim AC6XG

On Thu, 02 Oct 2003 09:25:38 -0700, Jim Kelley
wrote:



Gene Nygaard wrote:
What physical quantity do you think a grocery store scale measures?

You can probably figure that out for yourself, if you stop to think
about how they are tested and certified.

You misunderstand, Gene. It's not at all clear what _you_ think they
measure. I'm not asking about the units displayed on them. What
physical quantity do you think is actually being measured?

I think that is probably obvious to anybody with half a brain. But it
really doesn't matter, that shouldn't be any impediment to your
telling us where my clues have led you.

Where are you trying to lead me? Maybe you have some strange notion
of what the verb "to measure" means? It wouldn't hurt you to stop and
reflect on that for a moment, and answer it at least to yourself,
before you get to the "Open mouth, insert foot" stage.

And so a torque wrench has what kind of units printed on its scale -
mass and distance, or force and distance?

Once again, it doesn't cost you any more to pay attention.

They are units of force and distance,

There's the point.

Why are you still refusing to deal with the "meter kilograms" on my
torque wrench, even going so far as to dishonestly snip that out from
the middle of what you quoted, in between your own comments, without
telling us that you were doing so?

Since this involves only force and distance, what could it possibly
tell you about the existence of a unit of mass called a kilogram?
Since this involves only force and distance, what could it possibly
tell you about the existence of a unit of mass called a pound?

That the poundal system is much older than the slug system is merely
one of the many clues as to which is older, the pound mass or the
pound force.

Ah, older. So that means.........what?

Let's not overlook the obvious. Perhaps most the most important thing
for your education, and that of several other fools in this thread as
well, that it exists. That's something you weren't willing to admit
in the beginning. But if it didn't exist, we certainly wouldn't be
able to say that it is older. (A corollary, of course, is that if
pound force didn't exist, there would be nothing for these units to be
older than.)

Thus, what you quoted from the appendix of Halliday and Resnick (1981)
was incorrect. Do you agree?

That it is legitimate. Conversely, that it is the pound force that is
the ******* child.

This is also one important factor in the usage rules as spelled out by
the ASTM and followed by NIST, the U.S. national standards laboratory,
and the National Physical Laboratory, the U.K. national standards
laboratory. That is indeed one reason why this unit gets to use the
unadorned name "pound" and the original symbol "lb," while the newer
spinoff needs to be identified as a "pound force" and use the symbol
"lbf" to distinguish itself.

That the troy pounds, in terms of which the avoirdupois pound was
defined for centuries, are units of mass. This doesn't tell you that
they have never spawned units of force of the same name; you have to
figure that fact out by other means.
Gene Nygaard
http://ourworld.compuserve.com/homepages/Gene_Nygaard/

Gene Nygaard wrote:
"Why are you still refusing to deal with the "meter kilograms" on my
torque wrench---?"

Multiply the meters by 3.28 and multiply the kilograms by 2.2, and you
will have torque in their product computed in foot pounds. Or, just
multiply the dial reading by 7.22 for ft.lbs. Torque is the product of
force and distance.

Weight is a force produced by gravity on a particular mass.

The indication on a torque wrench is muscle force times lever length. It
directly has little relation to gravity in most torque wrench
applications.

Weight is the easy way to determine mass. Computing mass from collection
of acceleration data would be more complicated. M = F/A

Best regards, Richard Harrison, KB5WZI

On Thu, 2 Oct 2003 15:24:23 -0500 (CDT),
(Richard Harrison) wrote:

Gene Nygaard wrote:
"Why are you still refusing to deal with the "meter kilograms" on my
torque wrench---?"

Multiply the meters by 3.28 and multiply the kilograms by 2.2, and you
will have torque in their product computed in foot pounds. Or, just
multiply the dial reading by 7.22 for ft.lbs. Torque is the product of
force and distance.

It's no surprise that you don't have any problem with this. Don't you
remember when I told you that your views were at odds with those of
Jim Kelley (and half a dozen others in this thread as well)?

It's Jim Kelley who is having great difficulty dealing with these
"meter kilograms." Their existence demolishes one of his major
arguments. Will he, or any of the others making similar foolish
arguments, ever address this?

I don't think it's that you understand all this a whole lot better
than those others. Rather, you are more like those rocket scientists
who blissfully get specific impulse in "seconds" by using pounds mass
to cancel out pounds force. In SI, the units of specific impulse are
N·s/kg, or the equivalent m/s.

Weight is a force produced by gravity on a particular mass.

One definition of weight, yes.

The indication on a torque wrench is muscle force times lever length. It
directly has little relation to gravity in most torque wrench
applications.

I don't understand why you think that's even something worth bothering
to point out. Do you think this would have some bearing on the fact
that both Jim and I have characterized torque as "force times
distance"? How? The word "weight" didn't enter into those
discussions of torque, as far as I can remember.

Or are you just pointing out the unrelated (at least in the sense that
it wasn't part of our discussion of torque) fact that pounds force are
often used for things that are never called "weight," so identifying
them as "units of weight" is pretty stupid? At least, compared to the
identification of pounds mass as "units of weight" since in the
definition of weight as a synonym for the "mass" of physics jargon,
that's what mass units such as troy ounces or avoirdupois pounds or
kilograms are always used for--something that can be called "weight"?

Weight is the easy way to determine mass. Computing mass from collection
of acceleration data would be more complicated. M = F/A

Principle of equivalence. Look that up.

OTOH, computing force due to gravity with a balance is not merely
"more complicated," it is impossible without additional information
you don't get from the process of weighing it with the balance.

For example, suppose I have a bar of gold that weighs 401.23 troy
ounces on my balance. How much force does it exert due to gravity, at
my location on Earth? Use any force units you choose--poundals,
newtons, kilograms force, sthenes, whatever--just remember that troy
ounces are not units of force.

Now suppose I take the whole works to the middle of the Sea of
Tranquillity on the Moon, and weigh it again. It weighs 401.25 troy
ounces. How much force is it exerting due to gravity now? Once
again, any units of force will be fine.

Now, I'm also sure that you are well aware that we call what we
measure with a balance "weight," aren't you? Can you tell me why so
many science textbook authors appear to be unaware of this commonly
known fact? (They aren't really, it is a sham in most cases, and
others try to weasel out of it by imagining some "error" is that
usage.) Would you suppose that this might have something to do with
the great emphasis some of them place on the operation of a spring
scale, going into great detail about how they work, while ignoring the
only weighing devices anybody had ever used for the 7000 years or so
that people had been weighing things, before those spring scales first
appeared in the 19th century?

Gene Nygaard
http://ourworld.compuserve.com/homepages/Gene_Nygaard/

Gene Nygaard wrote:
It's Jim Kelley who is having great difficulty dealing with these
"meter kilograms." Their existence demolishes one of his major
arguments. Will he, or any of the others making similar foolish
arguments, ever address this?

If you have a point, sir, I think it's time you should make it. If your
intent is nothing more than to blither inanities, then when will you
have your fill?

73 de ac6xg

Gene Nygaard wrote:
So my followup to you is along the same lines: Do you claim that
those "meter kilograms" prove that kilograms are not units of mass?

Not a very difficult question to answer, is it, Jim?

Nope. As I recall, the reason it came up was that you were denying that
pounds were a unit of force. I cited the torque wrench, and you pointed
out that kg-f are also units of force. I still think you lose on that
account. Don't you?

73 ac6xg

On Fri, 03 Oct 2003 11:01:09 -0700, Jim Kelley
wrote:



Gene Nygaard wrote:
It's Jim Kelley who is having great difficulty dealing with these
"meter kilograms." Their existence demolishes one of his major
arguments. Will he, or any of the others making similar foolish
arguments, ever address this?

If you have a point, sir, I think it's time you should make it. If your
intent is nothing more than to blither inanities, then when will you
have your fill?

You can be pretty dense when you want to be.

Here's what you, Jim Kelley, wrote earlier in this thread:

Date: Fri, 26 Sep 2003 15:44:09 -0700
Message-ID:

Why do you think torque wrenches have the unit
'foot-pounds' printed on them if the pound is a unit
of mass?

Date: Wed, 01 Oct 2003 10:32:56 -0700
Organization: University of California, Irvine
Lines: 53
Message-ID:

And so a torque wrench has what kind of units printed on its
scale - mass and distance, or force and distance?

What was your point in asking these questions? Quite simple. You
were offering those "foot-pounds" as proof of the supposed fact that
pounds are units of force and not units of mass. In fact, you
specifically claimed, by asking a rhetorical question in last Friday's
message, that torque wrenches would not have these units on them if a
pound is a unit of mass.

So my followup to you is along the same lines: Do you claim that
those "meter kilograms" prove that kilograms are not units of mass?

Not a very difficult question to answer, is it, Jim?

Gene Nygaard
http://ourworld.compuserve.com/homepages/Gene_Nygaard/

On Fri, 03 Oct 2003 11:54:00 -0700, Jim Kelley
wrote:



Gene Nygaard wrote:
So my followup to you is along the same lines: Do you claim that
those "meter kilograms" prove that kilograms are not units of mass?

Not a very difficult question to answer, is it, Jim?

Nope. As I recall, the reason it came up was that you were denying that
pounds were a unit of force.

Then why did you claim something entirely different--not that this
proved that pounds force exist, but rather that it proved that pounds
could not be units of mass?

That official definition of a pound as a unit of force still remains
an elusive little devil, however. Don't you agree? Or are you good
enough to find it?

I cited the torque wrench, and you pointed
out that kg-f are also units of force. I still think you lose on that
account. Don't you?

Certainly not.

Thanks for correcting your earlier claims. You are making progress,
now admitting both that pounds are units of mass, and that kilograms
force exist just as well as pounds force do. Have you realized yet
that you are now aligning yourself with me, rather than with fools
like Richard Clark and KU2S, Raymond Sirois. With me, and with the
younger Resnick and Halliday (1960) that I quoted, not with the fools
you quoted, Halliday and Resnick (1981 appendix, and appendix of most
or all later editions).
Gene Nygaard
http://ourworld.compuserve.com/homepages/Gene_Nygaard/