From: Tony M on 18 May 2010 13:51 On May 18, 9:22 am, "Paul B. Andersen" <paul.b.ander...(a)somewhere.no> wrote: > On 12.05.2010 15:55, Tony M wrote: > > > > > > > On May 12, 8:49 am, "Paul B. Andersen"<paul.b.ander...(a)somewhere.no> > > wrote: > >> On 12.05.2010 07:02, Koobee Wublee wrote: > > >>> Let's bring back the two > >>> equations describing energy, mass, and momentum below. > > >>> *1* E^2 = m^2 c^4 + p^2 c^2 > >>> *2* E^2 = m'^2 c^4 > > >>> Where > > >>> ** m = Rest mass > >>> ** m' = Observed mass > >>> ** p = Observed momentum > > >>> These equations are actually identical, but there are always bevies of > >>> Einstein Dingleberries who would aloofly swear to their god Einstein > >>> the nitwit, the plagiarist, and the liar that equation *1* is the only > >>> one that is any valid. > > >> They are identical for massive objects only. > >> What does *2* say the energy of a photon is? > >> Is it correct? > > >> -- > >> Paul > > >>http://home.c2i.net/pb_andersen/-Hide quoted text - > > >> - Show quoted text - > > > It says the energy of a photon is equal to its observed (or > > relativistic) mass (not the rest mass) multiplied by c^2. > > And yes, it is very correct. > > A massless particle has no 'relativistic mass'. > The 'mass equivalent' of its energy, h*nu/c^2 > is not the same as 'relativistic mass'. > > -- > Paul > > http://home.c2i.net/pb_andersen/- Hide quoted text - > > - Show quoted text - The mass of a photon is E/c^2, whatever words you choose to describe it. One can call it observed mass because it is observer dependent or relativistic mass because it is relative to the observer. The term relativistic does not imply a gamma factor; it just means that observers with relative velocities to each other will measure or observe different values for that same quantity.
From: Androcles on 18 May 2010 13:59 "Tony M" <marcuac(a)gmail.com> wrote in message news:235e51cf-110e-4a6b-bc63-3eefd52bbc14(a)40g2000vbr.googlegroups.com... On May 18, 9:22 am, "Paul B. Andersen" <paul.b.ander...(a)somewhere.no> wrote: > On 12.05.2010 15:55, Tony M wrote: > > > > > > > On May 12, 8:49 am, "Paul B. Andersen"<paul.b.ander...(a)somewhere.no> > > wrote: > >> On 12.05.2010 07:02, Koobee Wublee wrote: > > >>> Let's bring back the two > >>> equations describing energy, mass, and momentum below. > > >>> *1* E^2 = m^2 c^4 + p^2 c^2 > >>> *2* E^2 = m'^2 c^4 > > >>> Where > > >>> ** m = Rest mass > >>> ** m' = Observed mass > >>> ** p = Observed momentum > > >>> These equations are actually identical, but there are always bevies of > >>> Einstein Dingleberries who would aloofly swear to their god Einstein > >>> the nitwit, the plagiarist, and the liar that equation *1* is the only > >>> one that is any valid. > > >> They are identical for massive objects only. > >> What does *2* say the energy of a photon is? > >> Is it correct? > > >> -- > >> Paul > > >>http://home.c2i.net/pb_andersen/-Hide quoted text - > > >> - Show quoted text - > > > It says the energy of a photon is equal to its observed (or > > relativistic) mass (not the rest mass) multiplied by c^2. > > And yes, it is very correct. > > A massless particle has no 'relativistic mass'. > The 'mass equivalent' of its energy, h*nu/c^2 > is not the same as 'relativistic mass'. > > -- > Paul > > http://home.c2i.net/pb_andersen/- Hide quoted text - > > - Show quoted text - The mass of a photon is E/c^2, whatever words you choose to describe it. =============================================== The mass of a kilowatt-hour is 3.6 megajoules / c^2, whatever words you choose to describe it. Perhaps your electricity meter should be graduated in milligrams.
From: Tony M on 18 May 2010 14:45 On May 18, 1:59 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > "Tony M" <marc...(a)gmail.com> wrote in message > > news:235e51cf-110e-4a6b-bc63-3eefd52bbc14(a)40g2000vbr.googlegroups.com... > On May 18, 9:22 am, "Paul B. Andersen" <paul.b.ander...(a)somewhere.no> > wrote: > > > > > > > On 12.05.2010 15:55, Tony M wrote: > > > > On May 12, 8:49 am, "Paul B. Andersen"<paul.b.ander...(a)somewhere.no> > > > wrote: > > >> On 12.05.2010 07:02, Koobee Wublee wrote: > > > >>> Let's bring back the two > > >>> equations describing energy, mass, and momentum below. > > > >>> *1* E^2 = m^2 c^4 + p^2 c^2 > > >>> *2* E^2 = m'^2 c^4 > > > >>> Where > > > >>> ** m = Rest mass > > >>> ** m' = Observed mass > > >>> ** p = Observed momentum > > > >>> These equations are actually identical, but there are always bevies of > > >>> Einstein Dingleberries who would aloofly swear to their god Einstein > > >>> the nitwit, the plagiarist, and the liar that equation *1* is the only > > >>> one that is any valid. > > > >> They are identical for massive objects only. > > >> What does *2* say the energy of a photon is? > > >> Is it correct? > > > >> -- > > >> Paul > > > >>http://home.c2i.net/pb_andersen/-Hidequoted text - > > > >> - Show quoted text - > > > > It says the energy of a photon is equal to its observed (or > > > relativistic) mass (not the rest mass) multiplied by c^2. > > > And yes, it is very correct. > > > A massless particle has no 'relativistic mass'. > > The 'mass equivalent' of its energy, h*nu/c^2 > > is not the same as 'relativistic mass'. > > > -- > > Paul > > >http://home.c2i.net/pb_andersen/-Hide quoted text - > > > - Show quoted text - > > The mass of a photon is E/c^2, whatever words you choose to describe > it. > =============================================== > The mass of a kilowatt-hour is 3.6 megajoules / c^2, whatever words you > choose to describe it. Perhaps your electricity meter should be graduated > in milligrams.- Hide quoted text - > > - Show quoted text - Thats what current theory tells us (whether right or wrong). If a body radiates 1kWh of energy its mass will decrease by 1kWh/c^2. The radiated energy carries 1kWh/c^2 amount of mass.
From: Androcles on 18 May 2010 15:05 "Tony M" <marcuac(a)gmail.com> wrote in message news:e26af12f-920c-4026-84ce-506c9c025caa(a)q33g2000vbt.googlegroups.com... On May 18, 1:59 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > "Tony M" <marc...(a)gmail.com> wrote in message > > news:235e51cf-110e-4a6b-bc63-3eefd52bbc14(a)40g2000vbr.googlegroups.com... > On May 18, 9:22 am, "Paul B. Andersen" <paul.b.ander...(a)somewhere.no> > wrote: > > > > > > > On 12.05.2010 15:55, Tony M wrote: > > > > On May 12, 8:49 am, "Paul B. Andersen"<paul.b.ander...(a)somewhere.no> > > > wrote: > > >> On 12.05.2010 07:02, Koobee Wublee wrote: > > > >>> Let's bring back the two > > >>> equations describing energy, mass, and momentum below. > > > >>> *1* E^2 = m^2 c^4 + p^2 c^2 > > >>> *2* E^2 = m'^2 c^4 > > > >>> Where > > > >>> ** m = Rest mass > > >>> ** m' = Observed mass > > >>> ** p = Observed momentum > > > >>> These equations are actually identical, but there are always bevies > > >>> of > > >>> Einstein Dingleberries who would aloofly swear to their god Einstein > > >>> the nitwit, the plagiarist, and the liar that equation *1* is the > > >>> only > > >>> one that is any valid. > > > >> They are identical for massive objects only. > > >> What does *2* say the energy of a photon is? > > >> Is it correct? > > > >> -- > > >> Paul > > > >>http://home.c2i.net/pb_andersen/-Hidequoted text - > > > >> - Show quoted text - > > > > It says the energy of a photon is equal to its observed (or > > > relativistic) mass (not the rest mass) multiplied by c^2. > > > And yes, it is very correct. > > > A massless particle has no 'relativistic mass'. > > The 'mass equivalent' of its energy, h*nu/c^2 > > is not the same as 'relativistic mass'. > > > -- > > Paul > > >http://home.c2i.net/pb_andersen/-Hide quoted text - > > > - Show quoted text - > > The mass of a photon is E/c^2, whatever words you choose to describe > it. > =============================================== > The mass of a kilowatt-hour is 3.6 megajoules / c^2, whatever words you > choose to describe it. Perhaps your electricity meter should be graduated > in milligrams.- Hide quoted text - > > - Show quoted text - That�s what current theory tells us (whether right or wrong). If a body radiates 1kWh of energy its mass will decrease by 1kWh/c^2. The radiated energy carries 1kWh/c^2 amount of mass. ============================================ Current theory tells us mass can be converted to energy, not that the mass of a photon is E/c^2. Photons are energy. Photons are massless, whatever words you choose to describe it. m |--> E/c^2 (right), not m = E/c^2 (wrong). mc^2 |--> E (right), not E |--> mc^2 (maybe, but never observed). One cannot create some matter from F/a = m, either.
From: PD on 18 May 2010 16:09
On May 18, 2:19 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > > Present the evidence; all you need do is argue your case logically, > based on acceptable axioms, and I'll accept what you say. > When one teaches, two learn. > I'm quite willing to listen, but I'll jump down your throat and rip your > lungs out (metaphorically, of course) if you try to bullshit me. > > Able to follow? Sorry, but you're talking mathematics and philosophy, not physics. Cases in physics are not made by arguing logically from mutually acceptable axioms. If this is how you'd like to proceed with physics, then you're barking up the wrong tree. Physics does things a little differently. The proposer puts together a model that includes some axioms, whether the axioms or the model are considered acceptable or not. Quite often, the axioms are considered outlandish and contrary to conventional wisdom. So what? From that model and those *assumed* axioms, certain conclusions are deduced from them, including a number of conclusions that are distinct from other models and which can be directly or indirectly tested in experimental measurement. When a significant number of those distinguishing conclusions are found in accord with measurement, then this provisionally *forces* the acceptance of the model and the axioms, in that the model has demonstrated itself to be superior to competing models on the grounds of experimental confirmation. If you think that's a sucky way to do business, and you're not about to go along with that game plan, then that's fine, but you're no longer doing physics. PD |