instability

You should probably both try using google before making fools of yourselves. Weight is a vector. It has magnitude (quantity) and direction (down).

I still wanna see some sorta scientist agree with Thorks conclusion that an ounce is a vector quantity

Quote from: squevil on January 22, 2013, 03:38:19 PM

im not sure how you came to that conclusion

Because I know what shape the earth is. Its a massive advantage in debates like these. I need only point out the obvious to win.

I know this has probably been answered before, but how do planes fly in UA? Shouldn't the Earth accelerate into them? 

Weight is a vector. Ounce is a unit of measure. The W you used in your formula is the magnitude of weight, and it is a scalar. The g you used in your formula is also the magnitude of an acceleration, and it is a scalar.

In formulas, the vectors are shown in bold and with a small arrow on top. Since it is difficult to draw an arrow without a formula editor or something, I guess the bold symbols must be enough.

But you did insist on your original claim that "an ounce is a vector". If you want to get all riled up, then first show that an ounce is a vector, and then tell me how stupid I am.

"Ounce" is a unit of measure. It is not a vector (that is, the combination of a magnitude and a direction).

Until sometime in late 19th century or so there was usually no need to make a distinction between mass and weight. Almost nobody was thinking about weight in other planets, for example, and there were very few who could measure the difference in local gravitational pull between different locations on Earth.

This created the wrong assumption that weight and mass were the same, and worse, that "weight" is the right word for what your bathroom scale shows. But the bad use of the word "weight" is a language problem, not a physics problem. Still you will find this wrong use many dictionaries.

In English the use makes the meaning, and that means that "bad", for example, means "good" or "awesome" if Michael Jackson uses "bad" in this way in a song. But in physics, incorrect use does not change the meaning of a word. Mass is, in essence (and in everyday circumstances), the number of protons plus the number of neutrons of some object, and it is usually measured in kilograms, pounds, ounces, troy ounces or so.

Weight and force are defined as the combination of a mass and an acceleration, and are measured in Newtons, pounds-force,  kilograms-force and others, but not in any of the units for mass.

But saying that a unit of measure is a vector is something that can only come from Thork.

Quote from: RealScientist on January 23, 2013, 04:41:37 AM

Weight is a vector.

Are you drunk? ... Weight and gravity are vectors.

Quote from: Thork on January 23, 2013, 12:27:39 PM

Quote from: RealScientist on January 23, 2013, 04:41:37 AM

Weight is a vector.

Are you drunk? ... Weight and gravity are vectors.

So, this is the quality of your answers now?

I am not going to read the rest of your answer. But please tell me if someplace in it you are explaining how "ounce is a vector".

I think it's perhaps a little disingenuous not to consider the fact that weight is almost always talked about as a magnitude. I have yet to see a set of scales that report my 'weight' as a vector. I've never heard weight watchers talk about separate radial, zenithal and azimuthal slimmers of the week. Although I don't dispute that for dynamical calculations it does matter.

Quote from: bowler on January 23, 2013, 12:39:55 PM

I think it's perhaps a little disingenuous not to consider the fact that weight is almost always talked about as a magnitude. I have yet to see a set of scales that report my 'weight' as a vector. I've never heard weight watchers talk about separate radial, zenithal and azimuthal slimmers of the week. Although I don't dispute that for dynamical calculations it does matter.

It is a very acceptable simplification to say "my weight is ..." instead of saying "the magnitude of my weight is ...". It would be even better, scientifically speaking, to say "right now I am pressing the floor with a force (or weight) of ..."

What is totally wrong, and comes from antique errors in the English and other languages that were never corrected, is to say that I weigh 100 kilograms, or that I weigh 220 pounds. It would be correct, according to the SI system of units, to say that I weigh 100 kilograms-force, or 220 pounds-force.

Remember, nobody cares about his weight to a precision better than 0.5%, because even if you pee you lose more than 0.1% of your weight, and if you have a good lunch you temporarily add about 0.5% to your weight. Therefore nobody cares that you are lighter in Mexico than in Helsinki.

But if you have even a wish to think as a scientist you have to correct your language and tell things as they are: if you show 100 kilograms on the scale, your mass is 100 kilograms, not your weight. Your weight is 981 Newtons or 100 kilograms-force in magnitude. You cannot do a very precise experiment without taking this into account.

And if you want to be a scientist, you will never mistake a unit of measure with a magnitude or a vector. You never mistake the measurement with the measuring equipment or scale.

Quote from: bowler on January 23, 2013, 12:39:55 PM

I think it's perhaps a little disingenuous not to consider the fact that weight is almost always talked about as a magnitude. I have yet to see a set of scales that report my 'weight' as a vector. I've never heard weight watchers talk about separate radial, zenithal and azimuthal slimmers of the week. Although I don't dispute that for dynamical calculations it does matter.

It is a very acceptable simplification to say "my weight is ..." instead of saying "the magnitude of my weight is ...". It would be even better, scientifically speaking, to say "right now I am pressing the floor with a force (or weight) of ..."

What is totally wrong, and comes from antique errors in the English and other languages that were never corrected, is to say that I weigh 100 kilograms, or that I weigh 220 pounds. It would be correct, according to the SI system of units, to say that I weigh 100 kilograms-force, or 220 pounds-force.

Remember, nobody cares about his weight to a precision better than 0.5%, because even if you pee you lose more than 0.1% of your weight, and if you have a good lunch you temporarily add about 0.5% to your weight. Therefore nobody cares that you are lighter in Mexico than in Helsinki.

But if you have even a wish to think as a scientist you have to correct your language and tell things as they are: if you show 100 kilograms on the scale, your mass is 100 kilograms, not your weight. Your weight is 981 Newtons or 100 kilograms-force in magnitude. You cannot do a very precise experiment without taking this into account.

And if you want to be a scientist, you will never mistake a unit of measure with a magnitude or a vector. You never mistake the measurement with the measuring equipment or scale.

Perhaps I don't understand how scales work. I assumed that in the factory a series of objects with known MASS were used to calibrate the scale on the display. Therefore although the scales measure force as long as the local g-value is more or less the same as the factory you will get the correct answer, as actually we incorrectly use weight. Maybe they do just measure force and incorrectly use kg for weight. Although I thought they typical weight of a human was about 700 N at sea level.

Thork you are so thick you make me want to break my monitor. AN OUNCE IS A UNIT OF MASS. MASS IS SCALAR!!!

troy weight, traditional system of weight in the British Isles based on the grain, pennyweight (24 grains), ounce (20 pennyweights), and pound (12 ounces). The troy grain, pennyweight, and ounce have been used since the Middle Ages to weigh gold, silver, and other precious metals and stones.

Definition of 'Troy Ounce'
A unit of measure for weight that dates back to the Middle Ages. Originally used in Troyes, France, the troy ounce was used when dealing with precious metals.

noun
a unit of weight equal to one sixteenth of a pound (avoirdupois);

Either that or all the scientists an engineers in the world are wrong.
Look. IN laymans terms your quite correct to refer to an ounce as weight.
But If your talking science. your kg's ounces, and grams are called mass. Weight is simply the force of gravity acting downwards on an object. THese are very different things

Quote from: Dinosaur Neil on January 22, 2013, 03:07:52 PM

Yes. If a troy ounce is the same everywhere, it is a measurement of mass.

wat? That's some pretty fancy circular reasoning right there. It is a unit of weight. That is a fact. It is a troy weight. It is not a mass. Changing location does not change the units. Mass is a scalar, it has magnitude. Weight is a vector. It has both magnitude and direction. Moving it around the earth does not magically turn it into a scalar.

Quote from: Dinosaur Neil on January 22, 2013, 03:07:52 PM

You stated it is not a measurement of mass. That's having it both ways.

Its not a measurement of mass. I just told you. Its a weight. An ounce is a vector. It has magnitude and direction.

W = m * g

Now, the fact that W remains constant all over earth (W is directly proportional to price of gold) and m stays the same because the number of atoms remains finite. So g isn't changing either or it messes up the equation.

I'm going to find it hard to dumb this down any more, so please read my post several times before asking any further questions.

You are right and the Encyclopaedia Britannica is wrong, I suppose?

I'm glad you know what is what and its the world's most famous Encyclopaedia that is full of misconceptions. 

Quote from: bowler on January 19, 2013, 02:39:19 PM

No - what I showed is much simpler than that. The acceleration due to gravity is slightly different around the Earth - this is a matter of fact.

Yeah, of course we all disagree with that so then using that to prove us wrong is a bit pointless. We have UNIVERSAL acceleration which is a constant.

Unlike the round earth constant 'gravity' that is apparently not constant at all. Instead you claim it to be a variable. So if your constants aren't constant, might we assume at least that your variables vary?

Yet its our theory with all the flaws.

Quote from: Thork on January 19, 2013, 02:42:34 PM

Quote from: bowler on January 19, 2013, 02:39:19 PM

No - what I showed is much simpler than that. The acceleration due to gravity is slightly different around the Earth - this is a matter of fact.

Yeah, of course we all disagree with that so then using that to prove us wrong is a bit pointless. We have UNIVERSAL acceleration which is a constant.

Unlike the round earth constant 'gravity' that is apparently not constant at all. Instead you claim it to be a variable. So if your constants aren't constant, might we assume at least that your variables vary?

Yet its our theory with all the flaws.

Ok. So this seems to be fairly close to the root of the problem. G is a constant with a value of 6.67384*10^-11 m³ kg^-1 s^-2 (same value in N m² kg^-2). g is a variable calculated by GM/r². Now given that M, the mass of the Earth, is constant, the only variable is r, the distance from the center of the Earth. Given the size of the Earth, I'm sure we can agree that Δ(r^-2) would be some small, giving only minute changes in g, as shown in the tables that have been posted.

G is the Gravitational Constant, g is the Gravitational Field Strenght (N m^-1) or the Gravitaional Acceleration (m s^-2) {both little g's will have the same value). That clear things up?

-Why doesn't it catch up with things like planes?
-What happens when it get's to the speed of light?

• The Bernoulli Effect
• It won't