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"Karats" measured by weight or volume?



 
 
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  #11  
Old November 3rd 04, 08:40 AM
Carl 1 Lucky Texan
external usenet poster
 
Posts: n/a
Default

How is mass measured without acceleration?

Carl
1 Lucky Texan


chunk wrote:
Since in an alloy both components are in the same place, the gravitational
constant will be the same for both components so the ratio of their weight
will be the same as the ratio of their masses. Weight seems OK to use here.

Chunk

"Howard Fairchild" wrote in message
...

Dale,
Neither, as precisely, it is mass. The weight of an object = m (mass) x g
(acceleration of gravity).Weight is the force exerted by the mass of the
object due to gravitational attraction.
Depending upon where you are on the earth, the weight is not a constant,


but

mass Always is. (unless you are approaching the speed of light, which


isn't

likely)
Density has a buoyancy effect in the measurement of both mass and weight,
where differing densities of equal mass displace different volumes (and
masses) of air, but in your case, the difference will be immeasureable.


( I

do see the difference in my measurements, as I do take it into account


when

comparing very precise mass standards)
So, it's Mass...

More confusing facts:
1 ounce Gold = 31.1035 grams (Troy ounce) Precious metals only are
measured in Troy units
1 ounce Aluminum = 28.349523 grams (Avoirdupois ounce) Everything else is


in

A
1 pound Gold = 12 oz Troy = 373.242 grams
1 pound Aluminum = 16 oz Avoirdupois = 453.592368 grams

Howie
Metrology is my game.

"Don A. Gilmore" wrote in message
. ..

"Dale Hallmark" wrote in message
...

"Don A. Gilmore" wrote in message
...

Hi guys:

Are karats (like of gold) measured by weight or by volume? Most of
what

I

read implies that karats are measured by weight (24k being pure

gold),

but

that just doesn't make any sense. If karats are determined by

weight,

you

would have to know exactly what the alloying metals were to determine

it.

If karats were by volume, they would be universal, regardless of

alloying

elements.

Which is right?

Don
Kansas City


Neither weight nor volume. It is a measure of purity.
Take the karats and divide by 24 and multiply by 100
and you have percent Gold content.


You guys are not following me. The purity has to be measured somehow:
either weight or volume.

Here's an example. If I take one cubic inch of gold and one cubic inch


of

aluminum and mix them together I should get two cubic inches of alloy


that

has a purity of 12 karats (50% of 24), but ONLY if I'm measuring karats


by

volume.

One cubic inch of gold weighs .6969 lbs. One cubic inch of aluminum
weighs
.0975 lbs. So the total weight of the 2.0 cu. in. of alloy is .6969 +
.0975
= .7944 lbs. So the percentage of gold by WEIGHT would be

.6969 / .7944 = 87.7%

Gold accounts for 87.7% of the total weight of the alloy. This results


in

a
karat of

.877 x 24 = 21.05k (by weight)

which is nowhere close to the "volumetric" karat of 12k.

Now, let's say I mix one cubic inch of gold with one cubic inch of


copper.

Volumetrically I still have half gold, or 12k. But a cubic inch of


copper

weighs .3210 lbs. So the total weight of the alloy is .6969 + .3210 =
1.018
lbs. and the percentage of gold by WEIGHT is

.6969 / 1.018 = 68.5% = 16.4k

So by changing the alloying metal I have considerably changed the karat,
if
indeed we are to use weight to determine karat, even though the size of
the
resulting alloy (2.0 cu. in.) is the same.

Now do you get what I mean?

Don
Kansas City










--
to reply, change ( .not) to ( .net)
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  #12  
Old November 3rd 04, 10:03 AM
Ursula Butschal
external usenet poster
 
Posts: n/a
Default

Carl 1 Lucky Texan wrote:
How is mass measured without acceleration?



Rotating the masses an measuring the forces is one possibility.

Best whishes,
Heinrich Butschal


Carl
1 Lucky Texan


chunk wrote:

Since in an alloy both components are in the same place, the gravitational
constant will be the same for both components so the ratio of their weight
will be the same as the ratio of their masses. Weight seems OK to use here.

Chunk

"Howard Fairchild" wrote in message
. ..


Dale,
Neither, as precisely, it is mass. The weight of an object = m (mass) x g
(acceleration of gravity).Weight is the force exerted by the mass of the
object due to gravitational attraction.
Depending upon where you are on the earth, the weight is not a constant,


but


mass Always is. (unless you are approaching the speed of light, which


isn't


likely)
Density has a buoyancy effect in the measurement of both mass and weight,
where differing densities of equal mass displace different volumes (and
masses) of air, but in your case, the difference will be immeasureable.


( I


do see the difference in my measurements, as I do take it into account


when


comparing very precise mass standards)
So, it's Mass...

More confusing facts:
1 ounce Gold = 31.1035 grams (Troy ounce) Precious metals only are
measured in Troy units
1 ounce Aluminum = 28.349523 grams (Avoirdupois ounce) Everything else is


in


A
1 pound Gold = 12 oz Troy = 373.242 grams
1 pound Aluminum = 16 oz Avoirdupois = 453.592368 grams

Howie
Metrology is my game.

"Don A. Gilmore" wrote in message
...


"Dale Hallmark" wrote in message
...


"Don A. Gilmore" wrote in message
...


Hi guys:

Are karats (like of gold) measured by weight or by volume? Most of
what

I


read implies that karats are measured by weight (24k being pure

gold),


but


that just doesn't make any sense. If karats are determined by

weight,


you


would have to know exactly what the alloying metals were to determine

it.


If karats were by volume, they would be universal, regardless of

alloying


elements.

Which is right?

Don
Kansas City


Neither weight nor volume. It is a measure of purity.
Take the karats and divide by 24 and multiply by 100
and you have percent Gold content.


You guys are not following me. The purity has to be measured somehow:
either weight or volume.

Here's an example. If I take one cubic inch of gold and one cubic inch

of


aluminum and mix them together I should get two cubic inches of alloy

that


has a purity of 12 karats (50% of 24), but ONLY if I'm measuring karats

by


volume.

One cubic inch of gold weighs .6969 lbs. One cubic inch of aluminum
weighs
.0975 lbs. So the total weight of the 2.0 cu. in. of alloy is .6969 +
.0975
= .7944 lbs. So the percentage of gold by WEIGHT would be

.6969 / .7944 = 87.7%

Gold accounts for 87.7% of the total weight of the alloy. This results

in


a
karat of

.877 x 24 = 21.05k (by weight)

which is nowhere close to the "volumetric" karat of 12k.

Now, let's say I mix one cubic inch of gold with one cubic inch of

copper.


Volumetrically I still have half gold, or 12k. But a cubic inch of

copper


weighs .3210 lbs. So the total weight of the alloy is .6969 + .3210 =
1.018
lbs. and the percentage of gold by WEIGHT is

.6969 / 1.018 = 68.5% = 16.4k

So by changing the alloying metal I have considerably changed the karat,
if
indeed we are to use weight to determine karat, even though the size of
the
resulting alloy (2.0 cu. in.) is the same.

Now do you get what I mean?

Don
Kansas City











Grüße,
Heinrich Butschal

--
www.juwelen.online-boerse.org
www.meister-atelier.de
www.schmuckfabrik.de
www.medico.butschal.de

  #13  
Old November 3rd 04, 05:22 PM
Carl 1 Lucky Texan
external usenet poster
 
Posts: n/a
Default

Would any of those forces be attributes of acceleration or deceleration?
Wouldn't you need to accelerate them up to the rotational velocity?

Carl
1 Lucky Texan

Ursula Butschal wrote:
Carl 1 Lucky Texan wrote:

How is mass measured without acceleration?




Rotating the masses an measuring the forces is one possibility.

Best whishes,
Heinrich Butschal


Carl
1 Lucky Texan


chunk wrote:


Since in an alloy both components are in the same place, the gravitational
constant will be the same for both components so the ratio of their weight
will be the same as the ratio of their masses. Weight seems OK to use here.

Chunk

"Howard Fairchild" wrote in message
...



Dale,
Neither, as precisely, it is mass. The weight of an object = m (mass) x g
(acceleration of gravity).Weight is the force exerted by the mass of the
object due to gravitational attraction.
Depending upon where you are on the earth, the weight is not a constant,

but



mass Always is. (unless you are approaching the speed of light, which

isn't



likely)
Density has a buoyancy effect in the measurement of both mass and weight,
where differing densities of equal mass displace different volumes (and
masses) of air, but in your case, the difference will be immeasureable.

( I



do see the difference in my measurements, as I do take it into account

when



comparing very precise mass standards)
So, it's Mass...

More confusing facts:
1 ounce Gold = 31.1035 grams (Troy ounce) Precious metals only are
measured in Troy units
1 ounce Aluminum = 28.349523 grams (Avoirdupois ounce) Everything else is

in



A
1 pound Gold = 12 oz Troy = 373.242 grams
1 pound Aluminum = 16 oz Avoirdupois = 453.592368 grams

Howie
Metrology is my game.

"Don A. Gilmore" wrote in message
m...



"Dale Hallmark" wrote in message
...



"Don A. Gilmore" wrote in message
...



Hi guys:

Are karats (like of gold) measured by weight or by volume? Most of
what

I



read implies that karats are measured by weight (24k being pure

gold),



but



that just doesn't make any sense. If karats are determined by

weight,



you



would have to know exactly what the alloying metals were to determine

it.



If karats were by volume, they would be universal, regardless of

alloying



elements.

Which is right?

Don
Kansas City


Neither weight nor volume. It is a measure of purity.
Take the karats and divide by 24 and multiply by 100
and you have percent Gold content.


You guys are not following me. The purity has to be measured somehow:
either weight or volume.

Here's an example. If I take one cubic inch of gold and one cubic inch

of



aluminum and mix them together I should get two cubic inches of alloy

that



has a purity of 12 karats (50% of 24), but ONLY if I'm measuring karats

by



volume.

One cubic inch of gold weighs .6969 lbs. One cubic inch of aluminum
weighs
.0975 lbs. So the total weight of the 2.0 cu. in. of alloy is .6969 +
.0975
= .7944 lbs. So the percentage of gold by WEIGHT would be

.6969 / .7944 = 87.7%

Gold accounts for 87.7% of the total weight of the alloy. This results

in



a
karat of

.877 x 24 = 21.05k (by weight)

which is nowhere close to the "volumetric" karat of 12k.

Now, let's say I mix one cubic inch of gold with one cubic inch of

copper.



Volumetrically I still have half gold, or 12k. But a cubic inch of

copper



weighs .3210 lbs. So the total weight of the alloy is .6969 + .3210 =
1.018
lbs. and the percentage of gold by WEIGHT is

.6969 / 1.018 = 68.5% = 16.4k

So by changing the alloying metal I have considerably changed the karat,
if
indeed we are to use weight to determine karat, even though the size of
the
resulting alloy (2.0 cu. in.) is the same.

Now do you get what I mean?

Don
Kansas City









Grüße,
Heinrich Butschal



--
to reply, change ( .not) to ( .net)
  #14  
Old November 9th 04, 03:09 AM
Mr G H Ireland
external usenet poster
 
Posts: n/a
Default

Purity is always defined as the percentage by weight(mass) of the wanted
substance in the mixture.
9 karat gold implies that 100gms or ounces or pennyweights of the alloy
contains 3/8 gms, ounces or pennyweights of pure gold.
A 10gm piece of 9 carat gold made by alloying 3gm of pure gold with 7gm of
aluminium would not have the same volume as a piece made by alloying 3gm of
gole with 7gm of osmium (if that were possible); its density would be near
21,
The aluminium alloy would be much larger in volume, but would still be
9karat.

When percentages are assumed to be by volume, that is indicated by the
designation (% v/v). The coresponding (% w/w) is used occasionally, when it
is required to make absolutely clear that the weight percentage is implied.

Hope that helps to clarify the situation. - G.H.Ireland.

--
igor
_____________________________________________
Acorn RISC OS4
_____________________________________________



 




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