The Size of Avogadro's number
in [Physics]
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From: Patrizio on 17 May 2010 09:39 On 17 Mag, 14:49, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > "Patrizio" <patrizio.pan-2...(a)libero.it> wrote in message > > news:c3ae731f-8e05-437d-88f9-3b48ec08dc5c(a)y21g2000vba.googlegroups.com... > > > > > > > On 17 Mag, 09:24, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > >> "Angelo" <patri...(a)libero.it> wrote in message > > >>news:8c2be7d5-ca61-4376-a4dc-ff4828613e2f(a)q23g2000vba.googlegroups.com.... > > >> > On 17 Mag, 03:21, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > >> >> "Angelo" <patri...(a)libero.it> wrote in message > > >> >>news:30514610-9062-465b-a4a9-14caf0227187(a)l18g2000vbn.googlegroups.com... > >> >> On 15 Mag, 02:30, "hanson" <han...(a)quick.net> wrote: > > >> > [snip] > > >> >> Dear Hanson, (dear all), > > >> >> I share and sincerely appreciate all you said above > >> >> and think to recognize the original (new for most) > >> >> significance you pointed out (thanks, sincerely). > > >> >> Anyway, I'm personally convinced that N_A should > >> >> be more appropriately named 'amount of substance' > >> >> and should have physical dimensions of "particle/mole" > >> >> where 'particle' may be atoms or molecules, in the > >> >> simplest cases. > > >> >> Sorry for this adding that isn't in line with your main > >> >> theme (I thought to take just an advantage to express > >> >> that opinion of mine here). > > >> >> Could I have your valuable opinion(s)? > > >> >> Best regards, > >> >> Angelo > >> >> ==================================== > >> >> Anyway, I'm impersonally convinced that 'substance' should > >> >> be more appropriately named 'flubber' since nobody can tell > > >> > Sorry, I have some difficulties as to regards at a > >> > disambiguation of the term 'flubber' (please consider > >> > that I'm not a native English speaker). > > >> >> me what matter or mass is. Valuable opinion given. > > >> > Thank you for your valuable opinion, but you yourself > >> > (I think) can realise that this is of no use for me as it > >> > stands. > > >> > Best regards, > >> > Angelo > > >> Sorry, I have some difficulties as to regards at a > >> disambiguation of the term 'substance' (please consider > >> that I'm a native English speaker). > > >> Substance = water, air, earth... > >> earth = sand, soil, rock, chalk... > >> chalk = calcium carbonate with flint nodules... > >> calcium = 20 protons, 20 neutrons, 20 electrons. > >> proton = flubber > >> flubber = ? > >> electron = ? > >> 6 protons + 6 neutrons + 6 electrons = carbon > >> carbon + calcium = chalk > >> chalk = earth > >> earth = substance > >> substance = flubber > >> flubber = ? > > > Thank you for this effort of yours. > > >> Thank you for your personal conviction, but you yourself > >> can realise that this is of no use for me as it stands. > > > OK. I was referring to what you can read in Wikipedia: > >http://en.wikipedia.org/wiki/Chemical_substance > > > Best regards, > > Angelo > > Ah, but you sent your query to a physics newsgroup. I saw that the msg was in X-post between "sci.physics, sci.chem" and didn't mind to discard sci.physics. > We get a little deeper than chemistry-by-numbers. Sorry, translation or other words, please? (If it's not too much bother) > Wackypedia says: > "a substance's atomic or molecular mass in atomic mass units is the same as > its molar mass in grams. Because of this, one can measure the number of > moles in a pure substance by weighing it". > http://en.wikipedia.org/wiki/Mole_(unit) > > "weighing it" means measuring its force against gravity, but what is "it"? Obviously, I can't answer your last question (but think that I'm not the only one), same for "mass" or perhaps precisely for "matter". Although I learned by a lot of physicists that the "weighing it" is not a measure of the force of gravity (which instead can be reached with a dynamometer: suspending a body to a spring and seeing the elongation) the real measuring of mass is to be done by the 'balance' (two arms one 'in primis' or other equivalent devices). It's, of course an operational definition of mass, not an investigation on what mass is.
From: Martin Brown on 18 May 2010 05:35 On 17/05/2010 02:46, Angelo wrote: > On 17 Mag, 03:21, "Androcles"<Headmas...(a)Hogwarts.physics_z> wrote: >> "Angelo"<patri...(a)libero.it> wrote in message >> >> news:30514610-9062-465b-a4a9-14caf0227187(a)l18g2000vbn.googlegroups.com... >> On 15 Mag, 02:30, "hanson"<han...(a)quick.net> wrote: > > [snip] > >> Dear Hanson, (dear all), >> >> I share and sincerely appreciate all you said above >> and think to recognize the original (new for most) >> significance you pointed out (thanks, sincerely). >> >> Anyway, I'm personally convinced that N_A should >> be more appropriately named 'amount of substance' >> and should have physical dimensions of "particle/mole" >> where 'particle' may be atoms or molecules, in the >> simplest cases. >> >> Sorry for this adding that isn't in line with your main >> theme (I thought to take just an advantage to express >> that opinion of mine here). >> >> Could I have your valuable opinion(s)? >> >> Best regards, >> Angelo >> ==================================== >> Anyway, I'm impersonally convinced that 'substance' should >> be more appropriately named 'flubber' since nobody can tell > > Sorry, I have some difficulties as to regards at a > disambiguation of the term 'flubber' (please consider > that I'm not a native English speaker). You should be made aware that you are conversing with a netkook called Androcles. His opinions will not enlighten you at all. As far as we can tell gravitational attraction is consistent with the inertial mass of objects irrespective of their composition. The extention of the Eotvos experiment to different high purity materials by Roll, Krotov & Dicke supports the hypothesis that to a very good approximation inertial mass is a sensible measure. Androcles invents his "flubber" only to confuse you. The OP might find Wiki on Eotvos helpful http://en.wikipedia.org/wiki/E%C3%B6tv%C3%B6s_experiment And also the equivalence principle - a basic explanation online at: http://www.physicsdaily.com/physics/Equivalence_principle Mass has proved the hardest of M,L & T to connect directly to fundamental processes in nature and at the moment 1kg is still defined as a reference lump of platinum metal in Paris. However, the latest advances in ion cyclotron mass spectrometry look like they will provide a means to define mass measurement in similar terms to L and T. > >> me what matter or mass is. Valuable opinion given. > > Thank you for your valuable opinion, but you yourself > (I think) can realise that this is of no use for me as it > stands. It is no use to anybody. Regards, Martin Brown
From: Androcles on 18 May 2010 05:58 You should be made aware that you are conversing with a miserable fuckwitted bigot called Martin Brown. His opinions will not enlighten you at all, and nor will anyone's opinion. Opinions are like arseholes, everybody has one and they all stink. Contrary to Brown's opinion, Androcles has not voiced any opinion on matter. "Martin Brown" <|||newspam|||@nezumi.demon.co.uk> wrote in message news:hbtIn.10099$7d5.7034(a)newsfe17.iad... > On 17/05/2010 02:46, Angelo wrote: >> On 17 Mag, 03:21, "Androcles"<Headmas...(a)Hogwarts.physics_z> wrote: >>> "Angelo"<patri...(a)libero.it> wrote in message >>> >>> news:30514610-9062-465b-a4a9-14caf0227187(a)l18g2000vbn.googlegroups.com... >>> On 15 Mag, 02:30, "hanson"<han...(a)quick.net> wrote: >> >> [snip] >> >>> Dear Hanson, (dear all), >>> >>> I share and sincerely appreciate all you said above >>> and think to recognize the original (new for most) >>> significance you pointed out (thanks, sincerely). >>> >>> Anyway, I'm personally convinced that N_A should >>> be more appropriately named 'amount of substance' >>> and should have physical dimensions of "particle/mole" >>> where 'particle' may be atoms or molecules, in the >>> simplest cases. >>> >>> Sorry for this adding that isn't in line with your main >>> theme (I thought to take just an advantage to express >>> that opinion of mine here). >>> >>> Could I have your valuable opinion(s)? >>> >>> Best regards, >>> Angelo >>> ==================================== >>> Anyway, I'm impersonally convinced that 'substance' should >>> be more appropriately named 'flubber' since nobody can tell >> >> Sorry, I have some difficulties as to regards at a >> disambiguation of the term 'flubber' (please consider >> that I'm not a native English speaker). > > You should be made aware that you are conversing with a netkook called > Androcles. His opinions will not enlighten you at all. > > As far as we can tell gravitational attraction is consistent with the > inertial mass of objects irrespective of their composition. The extention > of the Eotvos experiment to different high purity materials by Roll, > Krotov & Dicke supports the hypothesis that to a very good approximation > inertial mass is a sensible measure. > > Androcles invents his "flubber" only to confuse you. > > The OP might find Wiki on Eotvos helpful > > http://en.wikipedia.org/wiki/E%C3%B6tv%C3%B6s_experiment > > And also the equivalence principle - a basic explanation online at: > > http://www.physicsdaily.com/physics/Equivalence_principle > > Mass has proved the hardest of M,L & T to connect directly to fundamental > processes in nature and at the moment 1kg is still defined as a reference > lump of platinum metal in Paris. However, the latest advances in ion > cyclotron mass spectrometry look like they will provide a means to define > mass measurement in similar terms to L and T. >> >>> me what matter or mass is. Valuable opinion given. >> >> Thank you for your valuable opinion, but you yourself >> (I think) can realise that this is of no use for me as it >> stands. > > It is no use to anybody. > > Regards, > Martin Brown
From: David Bostwick on 18 May 2010 13:06 In article <0777d4e9-d5a3-4dd4-b88f-f00e66256801(a)v12g2000prb.googlegroups.com>, jbriggs444 <jbriggs444(a)gmail.com> wrote: [...] > >Contrary to what physics jargon might suggest, the act of "weighing" >an object >normally means "determine the mass of the object". [My chemistry >teacher >objected to this disharmony and insisted that we use "mass" as a verb >to describe >the operation. 'Let us put the object on a scale and mass it'] > Mass does not change. Weight does, because weight is affected by the gravitational force on the mass. That's why the formula for inertia doesn't contain g, but only m and v. I'll "mass" the same on the Earth or the Moon, or in a space station, and I'll have the same inertia, but I definitely won't weigh the same. [...]
From: glen herrmannsfeldt on 18 May 2010 13:44
In sci.physics jbriggs444 <jbriggs444(a)gmail.com> wrote: (big snip) > Contrary to what physics jargon might suggest, the act of "weighing" > an object normally means "determine the mass of the object". > [My chemistry teacher objected to this disharmony and insisted > that we use "mass" as a verb to describe the operation. > 'Let us put the object on a scale and mass it'] > It really does not matter whether you use a spring or a balance. > You are measuring the same quantity. I disagree, but it does depend on how you do it... > In the case of a balance, you are comparing the unknown mass in the > test pan against a [set of] known mass[es] in the reference pan. (snip) > You are doing this based on an assumption that the arms are equal > and that the difference in the acceleration of gravity at the > one pan is [nearly] identical to the acceleration of gravity at the > other. (snip) > In the case of a spring scale or load cell, you are comparing the > unknown mass in the test pan against the set of known masses > that the scale was calibrated against. If you recalibrate often, then I agree. If not, then you are assuming that g is the same as at the time and location where it was last calibrated. If, for example, you take a balance and spring scale to the moon, you will find that the balance indicates the same mass as it would on earth, but the spring scale, previously calibrated on earth, does not. If the spring scale has fixed gradations, you usually only have the ability to shift the zero. One could take the ratio of readings with the test mass and a standard mass, but that is not the normal operational method for a spring scale. A balance measures a ratio of forces, a spring scale just force, though often calibrated as mass. -- glen |