What is a relativistic mass?
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Relativistic mass is kind of an old concept.  In relativity, energy has inertia associated with it.  An object that is moving has more energy than an object at rest, thus it has more "mass" when it is moving than it does when it is sitting still.  A lot of the old scientists used to differentiate between rest mass and relativistic mass.  The relativistic mass was the extra inertia that the object had due to its motion.  Nobody really thinks about it this way anymore.  Einstein advocated only introducing the concept of rest mass.  This is because the rest mass is the same no matter what your reference frame is, but two observers in different frames won't always agree on the relativistic mass.  When you have a chunk of gold moving at close to the speed of light relative to you, you don't have more gold than you did when you were at rest.  The gold atoms just appear heavier because of their kinetic energy.   Likewise you aren't creating more protons, the protons that you have just look heavier.
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Weight is a force.  The National Institute of Science and Technologiy defines it here as such.\nhttp://physics.nist.gov/Pubs/SP811/sec08.html\n\nA force is acceleration times mass.  Weight is the accleration due to gravity times mass.  On the Earth's surface, this is approximately:\n\nWeight = Mass x 9.8 meters/second^2\n\nFor a accurate conversion, you would need to use the acceleration due gravity minus the accelration due to centrifugal force at your exact location.  \n\nThis is why physicists more commonly use mass than weight to describe an object.
825050
Probably you mean the classical Galilei transformation.\nThe relativistic one is the Lorentz transformation.\nGrüss Ihnen.\n\nTh
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Newtonian motion appies to objects with small masses and at velocities much smaller than the speed of light.  This covers a lot of stuff, most everything we experience in our lives will fall into this category, and because of this, Newtonian physics can still be applied in most circumstances as a very good estimation of what is actually happening.\n\nEinstein's relativistic physics applies to very massive objects traveling at high velocities, but it also applies to everyday things aswell, low masses at low velocities.  Everything Newtonian motion covers, relativistic motion will work too, it is just more complicated.\nFor example, in everyday life, we dont care much about the tim dilation experienced while driving down the steet or that we are gaining relativistic momentum....but it is occuring, just in such a small amount it doesnt matter.\n\nThen again, you also look at it from a quantum mechanical point of view.  Quantum mechanics deals with things with very small masses.  Although all objects experience some quantum effects, for most ordinary objects, this is too negligible to matter, but for small things like electrons, we need to take it into account.
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Photons are mass-less elementary particles.  There is a famous, and simple, experiment to prove this.  A small pinwheel in a vaccum sealed light blub which is balanced on a pin can be made to spin in proportion to the amount of light that falls on the vanes of the pinwheel.  The vanes are colored alternatively black and white.  The white vanes reflect photons and the black vanes absorb them, so the thing spins like crazy, proving that the photons have enough energy and speed (momentum) to impart motion on the pinwheel.\n\nPhotons are said to have no 'intrinsic mass' which means they don't have mass when 'at rest.'  Of course photons are never 'at rest' so there's something called 'relativistic mass' which accounts for mass-like properties of things traveling at high speed (like the speed of light, which photons travel at).
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Short Answer:\n\nThe photon is generally accepted to be massless and experiments show that its mass is consistent with zero.\n\nLong Answer:\n\nLight is composed of photons so we could ask if the photon has mass.  The answer is then definitely "no": The photon is a massless particle.  According to theory it has energy and momentum but no mass and this is confirmed by experiment to within strict limits.  Even before it was known that light is composed of photons it was known that light carries momentum and will exert a pressure on a surface.  This is not evidence that it has mass since momentum can exist without mass.\n\nSometimes people like to say that the photon does have mass because a photon has energy E = hf where h is Planck's constant and f is the frequency of the photon.  Energy, they say, is equivalent to mass according to Einstein's famous formula E = mc2.  They also say that a photon has momentum and momentum is related to mass p = mv.  What they are talking about is "relativistic mass", an outdated concept which is best avoided Relativistic mass is a measure of the energy E of a particle which changes with velocity.  By convention relativistic mass is not usually called the mass of a particle in contemporary physics so it is wrong to say the photon has mass in this way.  But you can say that the photon has relativistic mass if you really want to.  In modern terminology the mass of an object is its invariant mass which is zero for a photon.\n\nIf we now return to the question "Does light have mass?" this can be taken to mean different things if the light is moving freely or trapped in a container.  The definition of the invariant mass of an object is m = sqrt{E2/c4 - p2/c2}.  By this definition a beam of light, is massless like the photons it is composed of.  However, if light is trapped in a box with perfect mirrors so the photons are continually reflected back and forth in the box, then the total momentum is zero in the box's frame of reference but the energy is not.  Therefore the light adds a small contribution to the mass of the box.  This could be measured - in principle at least - either by an increase in inertia when the box is slowly accelerated or by an increase in its gravitational pull.  You might say that the light in the box has mass but it would be more correct to say that the light contributes to the total mass of the box of light.  You should not use this to justify the statement that light has mass in general.\n\nIt might be thought that it would be better to regard the relativistic mass as the actual mass of photons and light, instead of invariant mass.  We could then consistently talk about the light having mass independently of whether or not it is contained.  If relativistic mass is used for all objects then mass is conserved and the mass of an object is the sum of the masses of its part.  However, modern usage defines mass as the invariant mass of an object mainly because the invariant mass is more useful when doing any kind of calculation.  In this case mass is not conserved and the mass of an object is not the sum of the masses of its parts.  For example the mass of a box of light is more than the mass of the box and the sum of the masses of the photons (the latter being zero).  Relativistic mass is equivalent to energy so it is a redundant concept.  In the modern view mass is not equivalent to energy.  It is just that part of the energy of a body which is not kinetic energy.  Mass is independent of velocity whereas energy is not.\n\nLet's try to phrase this another way.  What is the meaning of the equation E=mc2?  You can interpret it to mean that energy is the same thing as mass except for a conversion factor equal to the square of the speed of light.  Then wherever there is mass there is energy and wherever there is energy there is mass.  In that case photons have mass but we call it relativistic mass.  Another way to use Einstein's equati
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Well it is a bit technical, but let me try.\n\nThe equations of special relativity include a term that looks like gamma=sqrt[1-(v/c)^2] where v is the speed of the object, and c is the speed of light. The equations for relativistic mass. The equations for relative position. The equations for time in the moving frame. And so on. \n\nSometimes gamma is in the numerator. Sometimes gamma is in the denominator. Sometimes the gamma is squared. But it is in there a lot (you can look them up on wikipedia or any number of web sites).  \n\nThese equations have been verified over and over, in particle accelerators and other experiments. They also explain the Michelson-Morley experiment that provided evidence against the exisence of the ether. \n\nNow what what happens to gamma when v gets close to c?\n\nObviously, gamma gets very small. If you are dividing by gamma in the equations, you get huge numbers. So relativistic mass goes to infinity as v gets close to c, and time slows down and the object moving gets compressed front to back.\n\nWhat happens when v is exactly c? \n\nThen, time stands still, and the object's relativistic mass is infinite and it is infinitely thin. \n\nWhat happens when v is bigger than c?\n\nThen gamma becomes imaginary, and mass becomes complex and time becomes complex and so on. Obviously, a complex mass or a complex time have no meaning in our universe. \n\nThere are postulated objects called tachyons that go faster than c, but no one has ever reliably observed one. Distant galaxies can move away from us faster than c, but that is because no information is being transferred. Just like you can move a light source and make the spot of light very far away appear to move faster than c, but no information is being transferred. Relativity only restricts the speed of information transfer to be c or less. \n\nAre the equations of special relativity true? Well they fit the evidence we have. And until we have evidence that they do not fit, we use them.
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Approximately the mass of 2 billion solar masses.\n\np.s. Weight is a function of something in a gravitational field, what you really are asking about is mass.
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newton....and u better take care,..its not just any velocity ^2 but the velocity of light^2 which is a constant\nhey,...just sum extra info...if u like\nAccording to Einstein, matter and energy are just different forms of the same thing. In Einsteins theory a mass cannot be accelerated to a speed greater than that of light, hence if a mass is traveling at the speed of light and energy is added it must be converted to mass, hence any mass can be converted to energy equal to that mass x velocity squared with Vc=1. this formulae shows a relationship of the quantities of mass and energy, A conversion factor. \n\nThis is actually a restatement of F=MV^2 with a special relativity to c to describe the equivalence of mass and energy.
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there is a important factor that appears in the theory of relativity:\nit's called "gamma" (we use the greek letter usually).\nFor a body moving with the velocity v, we have \ngamma=1/squareroot(1-v^2/c^2) , where c is the velocity of light.\nas you can check, as v increases (but always being lower than c), gamma becomes bigger and bigger, tending towards infinity as v tends to c. You can also check than when v=0, gamma=1.\n\nIn non relativistic theory, the mass of a rod for example is called "m" and its length "L". In the point of view of the rod, m and L are constant. For an outside observer also...\nBut what the theory of relativity shows is that for the outside observer, the mass and length of a rod moving with a velocity v is no more m and L, but gamma*m and L/gamma.\nThus, if the velocity is much smaller than c (everyday experience), gamma~1 and nobody can see the difference, if the velocity increased a lot, gamma->iinfinity, and thus the mass also tends towards infinity and the length tends towards 0...  for the outside observer!    If you are the rod, your velocity compared to yourself is 0, so your "own gamma" is 1 and your length and mass, in YOUR point of view, is constant.\n\nthe theory of relativity shows that "basic" things such as the length, the mass (and even the time between two events) of an object depends on the observer. \n\nI hope I've been a bit helpful. Go on with your reading, don't be afraid if you do not understand everything at the first and even the tenth reading, that comes with experience...
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yes\n\nlet:\nMo = resting mass\nc = speed of light\nv = current speed\nsqrt = square root\n\nThen M (moving mass) = Mo/sqrt(1-v^2/c^2) = L*Mo\n\nL is the Lorentz Factor = 1/sqrt(1-v^2/c^2)\n\nM, the moving mass is called the relativistic mass\n\nNote the energy to move is E = L*Mo*c^2 so as v approaches c the Lorentz factor goes to infinity and so does E. Most people write E = Mc^2 but this M is equal to L*Mo\n\nAlso note that when you move (even at slow speeds) your mass goes up just a small fraction.\n\nThis leads us to the reusable nuclear bomb. Assume you make a nuclear bomb with not enough material (less than critcal mass), you put this bomb on a very fast plane. For the people on the plane the mass does not change so it never has critical mass, however, to observer on the ground (who sees the plane moving) the mass increases and goes over critical mass. So those people on the plane when they detonate the bomb it does not complete the reaction but to those on the ground it does. Think about the possibility...
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V = (v + u) / (1 + uv/c²)\n\nTry that. The velocities are quite high so relativistic. Haven't tried it yet though.\n\nNevermind, the velocites aren't nearly high enough to be relativistic. If it was km/s it would work.
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Mass is a measure of inertia and hence greater the mass greater is the inertia.\n The 10kg mass will have the greatest inertia....
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Mass is the amount of matter present in a body and is an intrinsic property of the body. Mass of an object remains the same always at any place.\n\nWeight on the other hand is the force which a given mass feels due to the gravity at its place. Weight is measured in units of Force like Newton (which is the SI unit of Force).\nIf your mass is 60 kgs then your weight is approximately 60 x 10 = 600 Newtons. This is because\n\nForce = mass x acceleration (From Newton's second Law)\n\nThus, weight = mass x acceleration due to gravity
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Energy equals mass times the speed of light squared
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E=m c^2\nEnergy=Mass &#92;times (speed of light)^2
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Mass is always mass in any situation. You can´t change the mass, you only can change some properties of the mass, such as, weight (according the gravity), quantity of cinetic energy (accordind the velocity of the mass), etc. But the mass is always the same mass!!!