according to (E=mc^2) mass increases with increase in velocity...where does this mass come from?practically..?
342507
E=mc^2 is a version of Einstein's famous Relativity equation. Specifically, it means that Energy is equal to Mass times the speed of light squared. In essence, it states that there is an equivalence between mass and energy. This simple statement has many profound implications... such as no object with mass can ever go faster than the speed of light!\n\nThe Energy:\nEnergy is measured in joules (J). How much energy is one joule? Not very much really. If you pick up a large apple and raise it above your head you will have used around one joule of energy in the process. On the other hand we use up huge amounts of energy every time we switch on a light. A 100 watt light bulb uses 100 joules of energy every second, i.e. one watt is one joule per second.\n\nThe Mass :\nMass is a measure of a body�s resistance to acceleration. The greater the mass the greater the resistance to acceleration, as anyone who has ever tried to push a heavy object knows. For our purposes here, we can also think of mass as the amount of matter in an object. Mass is measured in kilograms (kg), 1 kg is about the same as 2.2 pounds. Note that we haven�t said what the mass is composed of. In fact it could be anything. It doesn�t matter if we use iron, plastic, wood, rock or gravy. The equation tells us that whatever the mass is it can be turned into energy (whether it is practical to actually do so is another matter and will be dealt with in later pages in this series).\n\nThe speed of light:\nThe speed of light is close to 186,300 miles per second (300,000 km per second). In order to make the equation "work" we need to convert these numbers into units that are more suited to our purposes. In physics, speeds are measured in metres per second. This is usually abbreviated to ms-1; that is "metres times seconds to the minus one". Don�t worry if you don�t understand this notation. We could equally write m/s but using ms-1 makes the mathematics easier in the long run. Likewise, we could either say that the speed of light is 300,000,000 metres per second, or, as is more usual, express the same figure in scientific notation: 3 � 10^8 ms-1.\n I think the mass is dont increase the enrgy is relative with light speed and the mass is constant\nE=constant*C^2\n\nFor a long time the concept of "mass" had been like the concept of energy before the 19th century. There were a lot of different material substances around, but it was not clear how they related to each other, if at all.\n\nAntoine-Laurent Lavoisier, as much as anyone else, first showed that all the seemingly diverse bits of tree and rock and iron on Earth�all the "mass" there is�really were parts of a single connected whole. Through decades of meticulous experiments, aided by his able wife Marie Anne, Lavoisier proved that the substances that fill our universe can be burned, squeezed, shredded, or hammered to bits, but they won't disappear. The different sorts floating around just combine or recombine. The total amount of mass, however, remains the same. This principle�the law of conservation of mass�was one of the great scientific achievements of the 1700s.
118159
it increases its velocity if it has positive acceleration. In other words, if its velocity is in the same direction as its acceleration.
249306
Ask Einstein, the famous E=mc2 formula directly relates to your question.
985678
Incoming momentum = p1 = mv1\nOutgoing momentum = p2  = mv2\nChange in momentum = p2 - p1 = m(v2-v1)\nThis change occurs in time, t.\nRate of change of momentum = m(v2-v1)/t = impressed force, f.\nm=0.149 kg, v1 = 43.4 m/s, v2 = -48.7 m/s, t = 1.1x10^-3 sec\n\nf = m(v2-v1)/t\nYou do the arithmetic.
418356
If you want somebody to explain the entire theory of relativity....then that will take a while.  For the basic E=mc^2, where E=energy, m=mass, and c=speed of light (3x10^8 m/s), then in simple terms it means that a small amount of mass can give off large amounts of energy.  Another way of seeing it is by saying that mass is simply highly compressed (or smashed together) amounts of energy.
895733
Energy=Mass * (speed of light)^2
262268
KE = 1/2 m v^2, so if the velocity remains constant, the kinetic energy and mass are directly proportional.
1073443
e=mc2 is the Eienstein's famous equation of relativity. This equation only applies to very tiny particles, who can move with the speed of light. 'c' here is the speed of light which is a constant quantity. 'm' is the mass of the tiny parrticle.\nWhen a tiny particle moves with a velocity which is the square of velocity of light, it produces energy.\n\nSo, you might wonder why the solar energy is so poweful that we can even run a car.
81056
ja :), that's a good one. E=mc^2 talks about the equivalence between matter and energy; c is just the constant that joins them both ..you won't attain a c ¨velocity¨out of it ; you'll just have to use \n E=mc^2/(sqrt(1-(v/c)^2) ( Is it Lorenz transf?) and I think Xav was pretty clear with his explanation! :)
339047
It is just a reference to E=mc^2.  It can be through fission or fusion, so yes you are surely correct.
260158
Suppose you are accelerating due to the presence of some mass M and you are some distance r away from the mass. You yourself have mass m. Then we know that your gravitational potential energy is equivalent to your maximum kinetic energy. Thus GMm/r = (1/2)*mv^2, or v = Sqrt[2GM/r]. If you start far enough away, you can take r to be the radius of the mass you are accelerating towards and then v will be your velocity as you hit the ground, not accounting for relativistic effects. \nIf you are in a starship and using some sort of propulsion relative to some inertial space-time frame, you have an asymptotic upper limit of c as measured from any such  frame, from basic relativity theory.\nIf you are not moving relative to an inertial frame (ie., you are using a gravity drive as described in the source link), then your "velocity" is not limited by any theory in contemporary physics.
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Hound, did you intend this:\nE=Ea+Eb = (m^2) * (c^4) + (p^2) * (c^2)\nThis makes E = Ea^2 + Eb^2, no?\n\nAlso, an alternate, simple-minded, non-relativistic answer to why does KE = .5MV^2:\nE=F*D (Energy, Force, Distance)\nF=M*A (M is Mass, A is Acceleration)\nE=M*A*D \nD=.5*A*T^2 (T is time)\nV=A*T\nE=M*A*.5*A*(V/A)^2=.5*M*V^2
1008175
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...
38506
yikes, everyone is giving you the wrong formula. it's not e=mc^2. that would be converting energy into mass and back which is done like when subatomic particles crash into each other really fast and such... the mass dialation formula you are looking for is \nm'= m/sqrt(1-v^2/c^2)\nwhere m' is the mass you would be not moving at the high velocities, m is the mass moving at the high velocities, v is the velocity you're traveling at, c is the speed of light, sqrt means we're square rooting everything in those parenthesis, and ^2 means squared. if you were to plug numbers in for velocity, you can see that this effect is absolutely neglagible unless you are moving very very close to the speed of light. and it is impossible to actually move at the speed of light, because then v^2/c^2 would be 1, and 1-1=0 so you would have a 0 in the denominator of that equation, which is impossible.  that equation is actually very interesting in that it is part of the lorentz factor which also effects time and length. in fact, as you increase speeds close to the speed of light, not only does mass increase, but time moves slower for you and length shrinks.  I've had to derive these equations in physics class, it's very interesting to do it yourself and come up with the equation proving that things like velocity, mass, and length are affected by velocity.  but again, you need to be going very very close to the speed of light for the velocity to have any effect on these things.\n\nas far as practicality, instances of the lorentz factor have been proven. there are these particles that have a certain lifespan before they disintigrate.  so now, we know how fast they are going and we know how long before they disintegrate, so theoretically, we should easily be able to figure out how much distance they cover before they disintigrate, right? but somehow, the particles go a lot farther than they should... if we plug their velocity into the lorentz transformation formula however, and put in how far they should travel (but don't), they we come up with how far they actually do travel.  this proves the validity of the lorentz factor.\n\nthere is no practical application of the mass increase since objects of great mass would require way too much energy to accelerate to speeds great enough to see this effect, so therefore it can't really happen.. if ever it did though, the only thing this mass expansion would serve to do would be to limit time travel. i mean, if time is slowing down for us at high speeds, technically we could make it slow down so much so that it would be going slower for you than everyone else and so you could basically travel forward in time. but if your mass was expanding and length shrinking, then either the pressure would kill you, or your blood would get so dense it couldnt carry oxygen to your cells and that would kill you, so there goes the time travel thing.
237452
The correct answer is that for equal masses the center of mass changes at 1/2 the SUM of their velocities: i.e., 10.05 m/s is to the right in standard geometry, and -11.6 m/s is to the left (velocities are VECTOR quantities, remember?). So the center of mass changes by 1/2 (10.05 + (-11.6)) = 1/2 (-1.55) m/s = -0.775 m/s, or in lay terms, 0.775 m/s to the left. Just keep your magnitudes (speeds) labelled correctly (+ or -) and your final answer will, by its sign, tell you which way the center of mass is moving.\nFor unequal masses, m1 and m2, moving with velocities v1 and v2, just use (m1 x v1 + m2 x v2)/(m1 + m2). Again, keep your +/- velocity values intact. This is the general equation that applies to the equal mass situation (a) also.
10449
Energy equals mass times the speed of light squared.  It's a formula used to calculate the conversion between mass and energy.  For example, an atom has positive protons and neutral neutrons in the nucleus, so how do the protons stay together? well, there's binding energy which actually comes from the mass.  Also, particle physicists have been crashing particles together in a particle accelerator at very very high velocities, and the resulting particle is often bigger than the sum of the two original particles.  This is because some of their energy was converted into mass.  It takes a huge amount of energy to make a very small increase in mass.
960298
m1vi1+m2vi2 = m1vf1 + m2vf2\n\nWhere:\n\nm1 = mass of first object\nvi1 = initial velocity of object 1\nm2 = mass of object 2\nvi2 = initial velocity of object 2\nvf1 = final velocity of object 1\nvf2 = final velocity of object 2\n\nKeep in mind though that velocity is a vector quantity. That means that there is directional intent with each velocity. Overall, that means when you add the velocities, you have to take in account the sign (+/-) and the direction. The easiest way to add velocity vectors is to place the end of one velocity at the head of another one. It's difficult to explain the concept of vector addition (or subtraction) in text, so look it up on the web, or the link I'm providing.\n\nOh, and one more thing. Since it's an elastic collision, kinetic energy is conserved. that means K1i + K2i = K1f + K2f, where K = (1/2)(mv^2)\n\nIf kinetic energy is not conserved, then it's an inelastic collision.\n\nInelastic collisions only have momentum conserved.