A simple Q. but not a simple A,,
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From: Inertial on 28 Dec 2009 18:28 "Anti Vigilante" <antivigilante(a)pyrabang.com> wrote in message news:hhauip$e88$1(a)news.eternal-september.org... > On Mon, 28 Dec 2009 23:04:19 +1100, Inertial wrote: > >> "Y.Porat" <y.y.porat(a)gmail.com> wrote in message >> news:f443926e-9fb3-4d6a-9c85- > cae0fe2bfe63(a)a32g2000yqm.googlegroups.com... >>> On Dec 27, 1:59 am, Sam Wormley <sworml...(a)gmail.com> wrote: >>>> On 12/26/09 5:42 PM, Spencer Spindrift wrote: >>>> >>>> > Q.: How is it that a photon has momentum but no mass? >>>> > Or in other words how does light carry energy? As far as I >>>> > know momentum is a property of moving or spinning >>>> > mass. >>>> > A photon cannot have mass or it would be infinite at C.. >>>> >>>> > A.; ??? >>>> >>>> Some properties of photons based on measurements For inertial >>>> observers, photons propagate at c >>>> >>>> From the quantum mechanical perspective >>>> >>>> 1. photons are emitted (by charged particles) 2. photons >>>> propagate at c >>>> 3. photons are absorbed (by charged particles) >>>> >>>> Photon momentum >>>> p = hν/c = h/λ >>>> >>>> Photon Energy >>>> E = hν >>>> >>>> Particle Chart - Standard Model >>>> http://www.astro.wisc.edu/~heroux/images/Particle_chart.jpg >>>> >>>> Conservation of momentum holds. One way to measure photon momentum >>>> is to it to measure the change in momentum of what absorbs or emits >>>> a photon. >>> >>> ------------------- >>> the Planck constant HAS MASS !! >> >> No .. it has DIMENSIONS of mass. It doesn't HAVE mass .. it would need >> to be an actual physical entity to have mass. All it is is a numerical >> relationship between energy and frequency (and occurs in a number of >> formulas) .. the dimensions of it are simply what is required to make >> dimensional analysis work for the formula that expresses that >> proportionality. > > Except Newtons have dimensions of mass which multiplied by distance have > the value of Work which has the same dimensions as energy. Yes they do. That doesn't mean work if an entity that has a mass. > What's the point of dimensional analysis if you can just wave it all away > by claiming it's purely mathematical? No-one said to wave it away. There is a difference between a number having dimensions of mass, and saying it has mass. It can't have mass .. its jsut a number. Its not a measurement of a physical entity. Its a numerical proportion. > Incidentally Energy also has dimensions of mass. Which is why the constant proportion 'h' has dimension of mass (among others) .. it is given whatever dimensions that are required to satisfy dimensional analysis.
From: Inertial on 28 Dec 2009 18:32 "Anti Vigilante" <antivigilante(a)pyrabang.com> wrote in message news:hhb5rj$gdk$1(a)news.eternal-september.org... >>> It can't reach c. >>> >>> Every experiment to find a mass for a photon has come up with zero (as >>> far as experiment can tell). >>> >>> What is the mass for a photon .. you seem to think formulas give it .. >>> you said we have momentum of a photon is >>> >>> p = m . c >>> >>> But we also have >>> >>> p = h / l >>> >>> where l is the wavelength of the photon, so >>> >>> m = h / l / c >>> >>> So you should be easily able to work out what your claimed mass for a >>> photon >>> of a given frequency and wavelength is (save some gamma radiation, with >>> wavelength of order of 10x-16). >>> >>> Do a calculation and see. >>> >>> Of course .. you'll find the the mass of a photon then varies depending >>> on who observes it, because its energy and momentum are observer >>> dependant. >>> >>> How do you explain the rest mass of a single photon varying like that >>> .. if >>> there is only one mass? >>> > > Simple the variation comes from the varying quantity namely frequency. > Since mass does not vary therefore the mass comes from Planck's constant. Exactly .. its just the mass part of a constant. It is not photon mass. Saying that 'h' has dimensions of mass does NOT prove a photon has mass. Its a nonsensical argument. > Question is what the hell does frequency have to do with energy? See Quantum physics for answers (though they aren't easy to understand :)). its the Energy transmitted by a wave / photon of that frequency. You can (very rough analogy) imagine shaking a rope to make a wave in it .. you need to put more energy into the shaking to make it shake faster :):) > Frequency implies cyclical behavior. Indeed it does (though I'm sure someone will come up with something that isn't :)).
From: Androcles on 29 Dec 2009 01:11 "Anti Vigilante" <antivigilante(a)pyrabang.com> wrote in message news:hhbr9h$ab1$1(a)news.eternal-september.org... >>> Simple the variation comes from the varying quantity namely frequency. >>> Since mass does not vary therefore the mass comes from Planck's >>> constant. >>> >>> Question is what the hell does frequency have to do with energy? >>> Frequency implies cyclical behavior. >> ================================================= The faster the wheel >> turns the faster it travels the road. The bigger the wheel the slower it >> needs to turn. > > That's an interesting angle. http://www.androcles01.pwp.blueyonder.co.uk/AC/AC.gif In this model of a coil and a capacitor, an alternating current (AC) is shown. Electrical charges build up on one side of the capacitor, producing an electrical field between the plates of the capacitor as shown by the dark arrows. When the capacitor can hold no more charge the current reverses and gradually increases, driving a magnetic field (shown by the N and S for North and South) until the current reaches a maximum and there is no more voltage across the plates of the capacitor. Having exhausted the potential energy of the voltage the magnetic field now begins to collapse and continues to push the current in the same direction, this time building up a voltage in the capacitor with opposite polarity, shown by the plus and minus signs. When the magnetic field is zero (as it must eventually become), the voltage is at a maximum and when the magnetic field is at maximum the current is also at a maximum and the voltage is at zero. Thus we see in the coil a kind of flywheel with inertia, reluctant to start moving and reluctant to stop once it is, and the capacitor is a kind of spring, eager to return from its stretched or compressed condition. On the right can be seen voltage (red/blue) and the magnetic field (gold/purple) with a teal vector representing constant energy. > >> If you insist it only has one speed then you'll be perplexed by the >> obvious. > > That's a whole other ball game. > Waves are history, photons are a ball game. http://www.androcles01.pwp.blueyonder.co.uk/AC/Photon.gif
From: Inertial on 29 Dec 2009 01:30 "Anti Vigilante" <antivigilante(a)pyrabang.com> wrote in message news:hhc6v4$e1o$1(a)news.eternal-september.org... > On Tue, 29 Dec 2009 10:32:01 +1100, Inertial wrote: > >> "Anti Vigilante" <antivigilante(a)pyrabang.com> wrote in message >> news:hhb5rj$gdk$1(a)news.eternal-september.org... >>>>> It can't reach c. >>>>> >>>>> Every experiment to find a mass for a photon has come up with zero >>>>> (as far as experiment can tell). >>>>> >>>>> What is the mass for a photon .. you seem to think formulas give it >>>>> .. you said we have momentum of a photon is >>>>> >>>>> p = m . c >>>>> >>>>> But we also have >>>>> >>>>> p = h / l >>>>> >>>>> where l is the wavelength of the photon, so >>>>> >>>>> m = h / l / c >>>>> >>>>> So you should be easily able to work out what your claimed mass for a >>>>> photon >>>>> of a given frequency and wavelength is (save some gamma radiation, >>>>> with wavelength of order of 10x-16). >>>>> >>>>> Do a calculation and see. >>>>> >>>>> Of course .. you'll find the the mass of a photon then varies >>>>> depending on who observes it, because its energy and momentum are >>>>> observer dependant. >>>>> >>>>> How do you explain the rest mass of a single photon varying like that >>>>> .. if >>>>> there is only one mass? >>>>> >>>>> >>> Simple the variation comes from the varying quantity namely frequency. >>> Since mass does not vary therefore the mass comes from Planck's >>> constant. >> >> Exactly .. its just the mass part of a constant. It is not photon mass. >> Saying that 'h' has dimensions of mass does NOT prove a photon has mass. >> Its a nonsensical argument. >> > > First of all the minute amount of mass it would represent is comfortably > close to zero. It doesn't represent ANY amount of mass. Its a number. its the ratio of photon energy to photon frequency. > It's close enough to be discussed. It's also a question of > where did that mass component come from? There is no mass component. its not an entity. It has no mass. It has the dimensions it does only so that dimensional analysis comes out correct. >>> Question is what the hell does frequency have to do with energy? >> >> See Quantum physics for answers (though they aren't easy to understand >> :)). its the Energy transmitted by a wave / photon of that frequency. >> You can (very rough analogy) imagine shaking a rope to make a wave in it >> .. you need to put more energy into the shaking to make it shake faster >> :):) > > That's not at all what I meant. But it is what you asked > I meant how does the energy determine the > angle at which the electron goes off at? That is nothing like what you asked. And has nothing to do with the equations or question being discussed. > That implies some complex > machinery under those fundamental particles. You're flying off on some wild unrelated tangent now.
From: Y.Porat on 29 Dec 2009 04:58
On Dec 29, 1:28 am, "Inertial" <relativ...(a)rest.com> wrote: > "Anti Vigilante" <antivigila...(a)pyrabang.com> wrote in message > > news:hhauip$e88$1(a)news.eternal-september.org... > > > > > On Mon, 28 Dec 2009 23:04:19 +1100, Inertial wrote: > > >> "Y.Porat" <y.y.po...(a)gmail.com> wrote in message > >> news:f443926e-9fb3-4d6a-9c85- > > cae0fe2bf...(a)a32g2000yqm.googlegroups.com... > >>> On Dec 27, 1:59 am, Sam Wormley <sworml...(a)gmail.com> wrote: > >>>> On 12/26/09 5:42 PM, Spencer Spindrift wrote: > > >>>> > Q.: How is it that a photon has momentum but no mass? > >>>> >     Or in other words how does light carry energy? As far as I > >>>> >     know momentum is a property of moving or spinning > >>>> > mass. > >>>> >     A photon cannot have mass or it would be infinite at C.. > > >>>> > A.; ??? > > >>>>   Some properties of photons based on measurements For inertial > >>>>   observers, photons propagate at c > > >>>>   From the quantum mechanical perspective > > >>>>    1. photons are emitted (by charged particles) 2. photons > >>>>    propagate at c > >>>>    3. photons are absorbed (by charged particles) > > >>>>   Photon momentum > >>>>    p = hν/c = h/λ > > >>>>   Photon Energy > >>>>    E = hν > > >>>>   Particle Chart - Standard Model > >>>>    http://www.astro.wisc.edu/~heroux/images/Particle_chart.jpg > > >>>>   Conservation of momentum holds. One way to measure photon momentum > >>>>   is to it to measure the change in momentum of what absorbs or emits > >>>>   a photon. > > >>> ------------------- > >>> the Planck constant  HAS MASS !! > > >> No .. it has DIMENSIONS of mass.  It doesn't HAVE mass .. it would need > >> to be an actual physical entity to have mass.  All it is is a numerical > >> relationship between energy and frequency (and occurs in a number of > >> formulas) .. the dimensions of it are simply what is required to make > >> dimensional analysis work for the formula that expresses that > >> proportionality. > > > Except Newtons have dimensions of mass which multiplied by distance have > > the value of Work which has the same dimensions as energy. > > Yes they do.  That doesn't mean work if an entity that has a mass. > > > What's the point of dimensional analysis if you can just wave it all away > > by claiming it's purely mathematical? > > No-one said to wave it away. > > There is a difference between a number having dimensions of mass, and saying > it has mass.  It can't have mass .. its jsut a number.  Its not a > measurement of a physical entity.  Its a numerical proportion. > > > Incidentally Energy also has dimensions of mass. > > Which is why the constant proportion 'h' has dimension of mass (among > others) .. it is given whatever dimensions that are required to satisfy > dimensional analysis. ------------------- dont you see that 'Inertial'(Ffeuerbacher) is an imbecile psychopath and crook as well ?? Y.P -------------------------- |