does photon has mass? justify ?
346637
Photon has mass so far it has energy but it depend on the nature of particle of ligth. You can apply this formula to get the mass of the photon; m = hf/c^2. (Where h=Planck's constant, f= frequency, c= speed of ligth)
557798
The rest mass of a photon is zero.\n\nTherefore its mass cannot increase whatever the speed it goes.\n\nBut its energy of motion increases.\n\nWhen it attains the speed C it has an energy of motion = h (Nu).\n\nSince energy can be converted to mass and mass can be converted to energy, this energy is equivalent to a mass mc^2.\n\nIn other words, the mass equivalent of photon is m = h (Nu)/ c^2\n\nIf you compare it with the motion of a mass, we can see some difference between the two. \n\nFor materials the rest mass is not zero. It has some initial mass m0. It increases with speed.\n\n The initial energy of this mass m0 is called energy of body and it is equal to m0 c^2; whereas for light it is zero. It has no energy of body.\n\nWhen the mass has reached a velocity V, let the mass be m. m > m0. \n\nNow the energy of body is mc^2. This is greater than m0 c^2;\n\nThe kinetic energy of the object is mc^ - m0 c^2. Note that it is not ½mV^2. \n\nWhen light is moving with this speed V, its energy of body is again zero. But its kinetic energy is h (Nu) C^2/ V^2.\n\nThus we see that the motion of an object is entirely different and cannot be compared with the motion of light. Yet we can find the mass energy relation by the formula mc^2.
554379
light.\n\nlet me refer you to e=mc2...light has mass energy and inertia.\na light is a wave and a particle.\nIt is in motion, and objects in motion have inertia and thusly power.\n\nThe true absence of light would exist in a vacuum. There is no pwer in a true vacuum. Even if the absence of light was "massive", that word you chose is a relative term, which is to say that massive CAN NOT imply mass, inertia, etc. The absence of light is NOT measurable because there is nothing there to exist.
979267
light has mass.light Is made of photon particles and they have mass.do you know the mass of light coming from sun on earth per day is about 30000 tons.yes it is true.photon particles has a very little mass but they do have and  that is why light has mass.and so it gets pulled by a black hole.only black holes have the needed g force to pull light back.light  travels so fast at approximate 300000km per second so it can't be pulled by other stars though they are huge
838380
Photons that travel at the speed of light have zero mass.  Photons are tiny packets of pure energy.  Theoretically photons could be converted to mass using Einstein's equation E = mc2 but would then be unable to travel at the speed of light.  Do photons really exist?  Enough of them in the UV range can give you a sunburn.
954004
No, not at all.\n\nProcesses in perfectly stationary nuclei turn mass into energy. For instance, the energy an emitted alpha particle has in alpha decay from a staionary nucleus is reflected by a tiny fall in mass of the nucleus.\n\nConversely, as you accelerate a particle towards the speed of light, more and more of the energy you give to the particle gets converted to mass. In fact, you can never get the particle to the speed of light - its mass will go to infinity first. This is quite measurable in a particle accelerator.
140934
Energy = mass times the speed of light squared\n\nIt conveys that a very small amount of matter actually represents/can be turned into a very large amount of energy, as in nuclear power, or a nuclear explosion.
815037
In fact, the answer to this question is YES. (Sort of)\n\nHere's why:\nEinstein's famous equation says that e=mc2. In other words, energy and mass are fundamentally linked (by the square of the speed of light, which is a very big number). When you put energy in to a dead battery, that is equivalent to putting in a tiny, tiny, tiny extra amount of mass. I doubt any set of weighing scales on the planet would be able to detect the difference it makes to your average AA however! \n\nFor all practical purposes though, provided your battery is a closed system and airtight, a charged battery has no more or less mass than a discharged one.
542466
Hey its very simple. It follows einstein's emergy mass relation viz. E=mc^2. Though photon is a massless particle but\nit has energy given by E=hv, v being the frequency. So the a part of photon's energy may be converted into mass and can give rise to massive charged particles like proton,electron etc. It can be understood from following equation:\n   E(photon) = m1*c^2 +m2*c^2 + 0.5*(m1*v1^2+m2*v2^2)\nIts notewrthy that the particles always appear in pair s.t. the two in a pair are of equal and opposite charges thus conserving the total charge.
810449
Technically, no since a photon is a massless quanta of light or electromagnetic radiation.  However, the whole wave-particle duality must come into play.  Energy from the Sun can impart a force upon objects--hence the whole solar sail project.\nAnother reason a photon cannot have any mass is because only a massless object can move at the speed of light.  Now, if you're wondering how can light rays be "bent" by gravity if gravity only affects mass, the light rays simply travel straight lines, unaffected by gravity.  However, since gravity warps or curves space, sometimes those straight lines get bent.
169241
I would have to say no. E=mc^2 is a version of einstein's relativity theory. It means that Energy is equal to Mass times the speed of light squared, and that there is an equivalence betwen mass and energy ( it means that no object with mass can go faster than the speed of light). But it has nothing to do with everything being made of nothing in my opinion. (see http://www.drphysics.com/syllabus/energy/energy.html)
417845
It has no mass. But it has relative mass of ≤ 1. It is a matter.
100574
There's more than one: light, a hole, darkness, and shadows to name a few.  Also a hallucination.\n\n*Yankeesrock26ws, air actually does have mass, it's just that it's effectively constant on Earth so we tend not to notice it.\n\nhandsome_stranger wrote:\n>>>actually light can be changed to mass so i think it is not a good >>>answer\nBut then it's not light anymore.
59698
It is not possible to experimentally measure something to have a value of exactly zero. The current limit on the mass of the photon is < 10^25 times lighter than the proton.\n\nThe idea of a particle's mass changing with velocity has not been used by serious physicists for several decades. We now rewrite the momentum equation as\nmomentum = gamma*mass*velocity , where the factor gamma describes the effect previously known as "relativistic mass".\n\nThe energy of a particle is \nenergy = gamma * mass * c^2 (try setting gamma=1 for a stationary particle) \nso we can write momentum = energy * velocity / c^2\nor momentum = energy/c  for particles moving at the speed of light.\nSo, even though a photon has zero (or very small) mass, it still has momentum, which it can transfer to an electron.
108368
Momentum of the speed of light=zero\nMomentum is defined as mass times speed.\n\nthe light don't have a momentum beacuse don't have a mass.  light is just energy.
687262
Light doesn't accelerate to that speed, it just propogates at that speed period.  Besides, F = ma says you need a mass to have an acceleration, and light, or photons, have zero mass.
192787
In its original form, the formula is\n\nE^2 = m^2 * c^4 + p^2 * c^2\n\nwhere E is the energy of the particle, m is its rest mass, p is its momentum and c is the speed of light.  If we're only concerned with how much energy is bound up in a certain mass, we say the mass is not moving and its momentum is zero (p = 0).  If this is the case:\n\nE^2 = m^2 * c^4 + (0)^2 * c^2\n\nE^2 = m^2 * c^4\n\nTake the square root of both sides and we get:\n\nE = mc^2\n\nThe full formula, with the momentum term included, works if we want to find the momentum of a photon.  For photons, m=0, so E = pc, or p = E/c.  \n\nEither way, the full form of the mass/energy equivalence formula is useful if something is at rest, or moving with a certain momentum.  E = mc^2  only works if the object is at rest.