So if energy can be converted to mass, and mass to energy...?

Question

This is like my third question, but if energy transforms into mass when you accelerate, can mass also be transformed into energy? In one of the answers someone told me the amount of mass was multiplied by the speed of light squared to get how much energy would come out if it. If it is possible, can you imagine what a massive amount of energy we could get of something the size of a car?!

Answer 1

The sun converts Helium into Hydrogen - the mass that is lost in the conversion is the source of the sun's energy. It is called fusion.

This virtually unlimited source of energy from mass is the reason there was such an enormous amount of excitement and enthusiasm a few years back when a group of scientists announced that they had created "cold fusion." Unfortunately, it was discovered later, when no other labs could duplicate the experiments, that it was either a hoax or really bad scientific procedure.

Fusion, in contrast to fission reactors in use today, could produce all the energy we need with no radioactive waste. Kind of like putting the power of the stars at our disposal.

I read once that the energy in a lump of coal, if its mass were converted to energy instead of merely burned, would light up New York for days - I don't recall the exact number of days - but it was astonishing. I suspect the "something the size of a car" you elude to in your question would create enough energy to satisfy our needs for quite some time.

Pretty impressive, this E=MC2, eh?

Answer 2

First, energy can never be created or destroyed, it can only be transformed from one form into another. So accelerating a mass to close to the speed of light (it can't go at the speed of light) doesn't create energy, it TAKES a lot of energy.

Second, physicists don't talk about relativistic mass anymore. We don't think you're really increasing the mass of an object by accelerating it. It's just that it takes more and more energy to get it to go closer and closer to the speed of light. So energy doesn't transform to mass when you accelerate. That "belief" came from the relativisitic equation for momentum: p=(gamma)*m*u, where gamma = 1/sqrt(1-u/c), and m is the (rest) mass. If you group (gamma)*m together you can define a relativistic mass m_r, so that p=(m_r)*u which looks like the classical equation. So m_r is an "effective" mass, not the real mass. Now we prefer to talk only about the invariant rest mass since
E^2 = p^2*c^2 + m^2*c^4 gives the total energy of the particle according to SR. Since energy and momentum are conserved quantities, m is a constant that depends only on the particle.


Now E=mc^2 tells you the energy contained in a mass. If you convert all the mass into another form of energy, E is how much you'd get. The only way we know to do that is to annihilate matter with antimatter. This does produce a lot of energy. It's impractical at present due to the difficulty in containing a significant amount of antimatter. There is a significant, but small amount of mass to energy conversion that takes place inside nuclear reactions. Though small in terms of mass loss, it packs a wallop of a punch - that's what nuclear weapons depend on.

It's important to realize that, philisophically, E=mc^2 doesn't talk about converting mass into energy and vice versa. It is instead saying that mass and energy are equivalent - they're two forms of the same thing.

Answer 3

You are correct, the amount of energy bound up in even a small amount of matter is incredibly large.

A U235 fissile reaction works like this. A neutron is fired into a U-235 atom creating a U-236 atom. U236 is unstable and immediately decays into atoms of Ba-141 (barium), Kr-92 (krypton), three neutrons, and energy [a respectable amount]. U236 has an atomic mass of 236.05. The combined mass of the decay products total 233.85. The mass difference (2.20) is converted to energy per the usual E = mc^2 rule [about 200MeV per atom].

From this you can see that when a Fission bomb detonates less than 1% of the mass is converted to energy. (And it takes about 13 pounds of U235 to make a bomb.)

Answer 4

That, according to Einstein's theory is possible to create energy if you place a mass and allow it to accelerate to the speed of light. As of today's technology however, no man made object comes close to traveling at the speed of light, so I would imagine that the energy created by something the size of a car traveling at the speed of light would be too huge to contain.
Of course, the theory of E=mc2 is the potential energy of a substance, I think the kinetic energy of this would be equal to E=mc2/sqrt(1-v2/c2)

Answer 5

Hi
there actually is a phsyical occurance where mass is converted to energy and back again.

Its called pair production and occurs naturally. In a vacuum, two gamma rays (light photons, i.e. massless energy) can collide to produce a positron and an electron. After production the two particles will annihilate each other and produce the gamma rays again, this occurs very rapidly, but happens.

Hope this helps

Answer 6

there isn't any frequent technique to transform warmth decrease back into chemical skill. this might violate the 2d regulation of Thermodynamics, which states that the entropy of the universe continually will strengthen with each and every spontaneous reaction, consequently, perpetual action is impossible. one ingredient i p.c. to show out even with the fact it is that mass isn't being converted to skill, particularly, the chemical skill saved interior the bonds is released as warmth, whilst the bonds are broken and reformed right into a state with much less skill skill. in case you may p.c. to talk over with the mass illness, the place some element of the nucleus of an atom exists as skill, then that's the place mass is truly converted to skill. i don't comprehend plenty approximately this (mass modern-day as a sort of skill) so i'm no longer gonna talk approximately it. study up on relativity in case you p.c. to comprehend greater.

Answer 7

Yes, I can imagine it, so what? Its too much to control and of no applicable value at this time.