How can mass be converted into energy

The loss of a nanogram is impossible to detect with any scale, so that's all theoretical. The strong force , weak force and electromagnetic force work together inside of a nucleus to create stable configurations of protons and neutrons. These nuclear processes make for much stronger forces than the electron recombination in the combustion of fossil fuels does.

This means that the release of energy from a nuclear reaction creates enough of a mass difference to be measured. Specifically, small amounts of mass are turned into energy from the breaking up fission or combination fusion of the nuclei of atoms. Even spontaneous radioactive decay converts a bit of mass into incredible amounts of energy.

By doing so, the energy from these processes can be used to generate electricity in nuclear power plants , or as nuclear weapons , which were first deployed in World War II and have only been tested since then nuclear weapons have since not been used as a direct attack, just very big threats. Although these reactions cannot convert the entire mass to energy, they still release tremendous amounts of energy.

See the page on energy density for more information. The sun uses fusion of hydrogen into helium to create sunlight at an astonishing rate.

The sun gives off 3. That means the sun is losing 4. First discovered by Einstein more than years ago, it teaches us a number of important things. We can transform mass into pure energy, such as through nuclear fission, nuclear fusion, or matter-antimatter annihilation. We can create particles and antiparticles out of nothing more than pure energy. And, perhaps most interestingly, it tells us that any object with mass, no matter how much we cool it, slow it down, or isolate it from everything else, will always have an amount of inherent energy to it that we can never get rid of.

But where does that energy come from? That's what Rene Berger wants to know, asking:. The sizes of composite and elementary particles, with possibly smaller ones lying inside what's Nuclear weapon test Mike yield The test was part of the Operation Ivy. A release of this much energy corresponds to approximately grams of matter being converted into pure energy: an astonishingly large explosion for such a tiny amount of mass.

Nuclear reactions involving fission or fusion or both, as in the case of Ivy Mike can produce tremendously dangerous, long-term radioactive waste. This explains why the Sun outputs so much energy; why nuclear reactors are so efficient; why the dream of controlled nuclear fusion is the "holy grail" of energy; and why nuclear bombs are both so powerful and so dangerous. It means that there exists a form of energy that cannot be taken away from a particle no matter what you do to it. So long as it remains in existence, this form of energy will always remain with it.

That's fascinating for a number of reasons, but perhaps the most interesting one is that all other forms of energy really can be removed. The rest masses of the fundamental particles in the Universe determine when and under what The properties of particles, fields, and spacetime are all required to describe the Universe we inhabit.

For example, a particle in motion has kinetic energy: the energy associated with its motion through the Universe. When a fast-moving, massive object collides with another object, it will impart both energy and momentum to it as a result of the collision, regardless of what else occurs.

This form of energy exists on top of the rest mass energy of the particle; it is a form of energy intrinsic to the particle's motion. But that's a form of energy that can be removed without changing the nature of the particle itself. Simply by boosting yourself so that you move with the same exact velocity magnitude and direction as the particle you're watching, you can decrease the total energy of that particle, but only down to a certain minimum.

An accurate model of how the planets orbit the Sun, which then moves through the galaxy in a Note that the planets are all in the same plane, and are not dragging behind the Sun or forming a wake of any type. If we were to move relative to the Sun, it would appear to have a lot of kinetic energy; if we moved with the same speed as it in the same direction, however, its kinetic energy would drop to zero. You might think that this means you can remove every form of energy other than rest mass energy, then, for any system at all.

All the other forms of energy you can think of — potential energy, binding energy, chemical energy, etc. Under the right conditions, these forms of energy can be taken away, leaving only the bare, unmoving, isolated particles behind.

You might be quick to answer "the Higgs," which is partially correct. Back in the early stages in the Universe, less than 1 second after the Big Bang, the electroweak symmetry that unified the electromagnetic force with the weak nuclear force was restored, behaving as one single force.

In fact, most neutrinos can pass completely through a star or planet without being absorbed. As we shall see, this behavior of neutrinos makes them a very important tool for studying the Sun. We now know that there are three different types of neutrinos, and in , neutrinos were discovered to have a tiny amount of mass. Indeed, it is so tiny that electrons are at least , times more massive. Ongoing research is focused on determining the mass of neutrinos more precisely, and it may still turn out that one of the three types is massless.

We will return to the subject of neutrinos later in this chapter. Some of the properties of the proton, electron, neutron, and neutrino are summarized in Table 1 Other subatomic particles have been produced by experiments with particle accelerators, but they do not play a role in the generation of solar energy. The nucleus of an atom is not just a loose collection of elementary particles. Inside the nucleus, particles are held together by a very powerful force called the strong nuclear force.

This is short-range force, only capable of acting over distances about the size of the atomic nucleus. A quick thought experiment shows how important this force is. Take a look at your finger and consider the atoms composing it.

Among them is carbon, one of the basic elements of life. Focus your imagination on the nucleus of one of your carbon atoms. It contains six protons, which have a positive charge, and six neutrons, which are neutral. Thus, the nucleus has a net charge of six positives. If only the electrical force were acting, the protons in this and every carbon atom would find each other very repulsive and fly apart.

The strong nuclear force is an attractive force, stronger than the electrical force, and it keeps the particles of the nucleus tightly bound together. In the same way, if particles come together under the strong nuclear force and unite to form an atomic nucleus, some of the nuclear energy is released. The energy given up in such a process is called the binding energy of the nucleus.

When such binding energy is released, the resulting nucleus has slightly less mass than the sum of the masses of the particles that came together to form it. In other words, the energy comes from the loss of mass. This slight deficit in mass is only a small fraction of the mass of one proton.

Figure 3. Fusion and Fission: a In fusion, light atomic nuclei join together to form a heavier nuclei, releasing energy in the process. Measurements show that the binding energy is greatest for atoms with a mass near that of the iron nucleus with a combined number of protons and neutrons equal to 56 and less for both the lighter and the heavier nuclei.

Iron, therefore, is the most stable element: since it gives up the most energy when it forms, it would require the most energy to break it back down into its component particles.

What this means is that, in general, when light atomic nuclei come together to form a heavier one up to iron , mass is lost and energy is released. This joining together of atomic nuclei is called nuclear fusion. Energy can also be produced by breaking up heavy atomic nuclei into lighter ones down to iron ; this process is called nuclear fission.

Nuclear fission was the process we learned to use first—in atomic bombs and in nuclear reactors used to generate electrical power—and it may therefore be more familiar to you. Fission also sometimes occurs spontaneously in some unstable nuclei through the process of natural radioactivity.

But fission requires big, complex nuclei, whereas we know that the stars are made up predominantly of small, simple nuclei. So we must look to fusion first to explain the energy of the Sun and the stars Figure 3. This will cause them to lose some of their mass, which then turns into energy.

However, every nucleus, even simple hydrogen, has protons—and protons all have positive charges. Since like charges repel via the electrical force, the closer we get two nuclei to each other, the more they repel.

But that striking distance is very tiny, about the size of a nucleus. How can we get nuclei close enough to participate in fusion? The answer turns out to be heat—tremendous heat—which speeds the protons up enough to overcome the electrical forces that try to keep protons apart. Inside the Sun, as we saw, the most common element is hydrogen, whose nucleus contains only a single proton.

Two protons can fuse only in regions where the temperature is greater than about 12 million K, and the speed of the protons average around kilometers per second or more.

In our Sun, such extreme temperatures are reached only in the regions near its center, which has a temperature of 15 million K. Even at these high temperatures, it is exceedingly difficult to force two protons to combine. This is, however, only the average waiting time. Since the Sun is about 4. Figure 4. Proton-Proton Chain, Step 1: This is the first step in the process of fusing hydrogen into helium in the Sun.

High temperatures are required because this reaction starts with two hydrogen nuclei, which are protons shown in blue at left that must overcome electrical repulsion to combine, forming a hydrogen nucleus with a proton and a neutron shown in red. Note that hydrogen containing one proton and one neutron is given its own name: deuterium. Also produced in this reaction are a positron, which is an antielectron, and an elusive particle named the neutrino. The Sun , then, taps the energy contained in the nuclei of atoms through nuclear fusion.

Deep inside the Sun, a three-step process takes four hydrogen nuclei and fuses them together to form a single helium nucleus. The helium nucleus is slightly less massive than the four hydrogen nuclei that combine to form it, and that mass is converted into energy. The initial step required to form one helium nucleus from four hydrogen nuclei is shown in Figure 4. In effect, one of the original protons has been converted into a neutron in the fusion reaction.

Electric charge has to be conserved in nuclear reactions, and it is conserved in this one. A positron antimatter electron emerges from the reaction and carries away the positive charge originally associated with one of the protons.

Since it is antimatter, this positron will instantly collide with a nearby electron, and both will be annihilated, producing electromagnetic energy in the form of gamma-ray photons. This gamma ray, which has been created in the center of the Sun, finds itself in a world crammed full of fast-moving nuclei and electrons.

The gamma ray collides with particles of matter and transfers its energy to one of them. The particle later emits another gamma-ray photon, but often the emitted photon has a bit less energy than the one that was absorbed. Such interactions happen to gamma rays again and again and again as they make their way slowly toward the outer layers of the Sun, until their energy becomes so reduced that they are no longer gamma rays but X-rays recall what you learned in The Electromagnetic Spectrum.

Later, as the photons lose still more energy through collisions in the crowded center of the Sun, they become ultraviolet photons. Figure 5.