Nuclear Physics

We need to back up a bit and lay a foundation for what sequential fission is. It begins in the nuclear physics lab (an accelerator facility) where we investigate nuclear events using heavy nuclei. We'll start there, and it'll be easy to understand what's up. Ready? Let's jump. We're big on investigating the mysteries of subatomic physics by smashing stuff. (Plus, it's fun!) One of our ideas was to take a fat atom like, say, lead, and make a bullet out of it. We'd strip off all its electrons (with really high voltage). Then we'd take the big positively charged nucleus and accelerate it in a big electromagnetic pump (an accelerator). With our bullet sufficiently speeded up, we'd slam it into something like, say, a uranium nucleus. In the collision event, a big "something" would form when the "lead was added to the plutonium" in the target area. Things then begin to happen. There are a number of events that could result when we try to glue two big, fat anomic nuclei together. First, they don't like to be stuck to gether. They decay. And fission is common. But what frequently happens is that our "resultant nucleus" fissions, then one or both of the fission fragments fission, and then one or more of those fragments fission. It's a sequence of fissions, and what actually happens will depend on what was combined and at what energies (as well as a good bit of probability as to what was actually created). Make sense? It's not that hard. It might help to build a "family tree" of events. And physicists do. Let's take the analogy. Grandparents don't have grandkids. They have kids who have kids which become the grandkids. It's sequential, and each "step" has a precursor event. Does that lock it in for you? It's just as simple as it seems. Really!

== If the question can be imagined and framed properly, it can be asked, even if it has no "real world" applications. But let's get real with this one. The answer is "not very far" into the lead shield. A sheet of aluminum foil would stop the pair of particles. We've got problems with this one. There isn't a handy table for looking up the slowing down length of lead for positrons across a range of positronic energies, but let's take a short detour. We need some review. A positron and an electron are created in pair production. You're already fairly familiar with the electron. It has a negative charge, doesn't weigh very much (has little mass), and when it's moving, it will have to contend with the orbiting electrons of all the atoms in its path of travel. (Even in air, there are a tons and tons of "speed bumps" in the way of our little electron.) The electron can't cope well with these "flocks" of critters of its own kind, even if it is of high energy. It will scatter and lose energy at just about every atom it encounters along its trajectory (if we can use that term). It takes little time, that is, it can't travel very darn far, before the "encounters" it has with anything it "bumps into", i.e., those scattering events, "suck" all the energy out of our little electron and it's left hanging. It has a very short mean free path in air. In any kind of liquid or solid, it's even shorter. A lot shorter. And it's the same with a positron - except that it will join an electron at some point along its journey and the pair will be mutually annihilated. A couple of hot gamma rays will leave the scene of the event. Even with a few MeV of energy, the mean free path of an electron and a positron is extremely short in air. Oh, and these particles will be traveling in oppositedirections when they are created. It isn't like they'd be moving as a pair in the same direction like cars in adjacent lanes on a freeway. What about plumbum? We're talking mean free path here - the mean free path of an electron and a positron in lead. What is the slowing down length for a positron or an electron at a couple of MeV in lead? Short. Very short. Very, very short. Laying out the problem mathematically would just be an exercise in probability and statistics. And forget about setting up an experiment to "prove" the calculated answer. Got a clever little application for running Monte Carlo calculations on your computer? Start identifying and defining your variables. And don't forget to include factors that deal with both inelastic andelastic scattering. You'll have both happening here 'cause it's "real world" stuff. So no fudging and leaving out elastic scattering possibilities. It's a physics grad student's nightmare. Good luck with all that. What about conducting an experiment? The only thing close to being effective at "looking" at the penetration power of the positron is probably a spectroscope or PET imager, but how are you going to use them? The spectroscope would be difficult to apply for the purpose here (impossible, probably), and the PET units can't "resolve" the tiny distances we're talking about. By the way, it is true that you'd only be looking at the annihilation events resulting from the positron's recombination with an electron in PET imaging. And the ability of those machines is a long way from having the kind of resolution you'd need to "see" results that you could measure. You'd doubtless have better luck with just calculating an answer.

A subatomic particle is something smaller than an atom. These are further broken up into elementary and composite subatomic particles.

Electrons are elementary, whereas protons and neutrons are composite and can still be further broken down.

Salt, sugar, and baking soda are examples of solids that dissolve in water. When these substances are mixed with water, they break down into molecules or ions and disperse throughout the water, forming a homogeneous solution.

The core of an atom is called the nucleus, which contains protons and neutrons. Protons are positively charged particles, while neutrons have no charge. The nucleus is surrounded by a cloud of negatively charged electrons that orbit around it in specific energy levels.

A strong attractive force between protons and neutrons

The alpha particle has a charge of +2e, where e is the elementary charge of a proton. This means the alpha particle has a positive charge of twice the charge of a single proton.

Jesus
The smartest man ever to live is Nick Rippy. Born in Colorado in 1980, doctors were amazed as he cut his own umbilical chord and told them that he could use some extra oxygen. When he was eight he moved with his mother to Mason Texas where he was voted most best Texan ever and most likely to rule the earth. Not long after that he graduated from Mason High School with a modest 3.26 gpa without ever attending a class. Next he moved to San Marcos Texas and quickly became " coolest man on campus". He turned down several offers of marriage as well as modeling careers to work with troubled children with his friend Eli King (best light bulb maker for 6 years). Nick is currently married to the sexiest woman alive ( Jaleen Rippy) and working in the oil field while he is working on the cure for cancer.

Radioactive, as applied to an atom, means the nucleus is unstable, and "wants" to change into something else, either by emitting particles or energy. or by absorbing particles or energy.

Answ2. Radioactivity is a one-way street. It only loses total energy.

BUT it is possible to add energy/mass to a simple atom; as obviously happens in super nova by the process of fission.

This can also be done in an linear accelerator by accelerating a mass and firing it into a target.

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The existence of antimatter was first predicted by physicist Paul Dirac in 1928 as a consequence of his Dirac equation, which unified quantum mechanics and special relativity. The first observation of antimatter particles, specifically positrons, was made by physicist Carl D. Anderson in 1932 while studying cosmic rays.

Yes, the daughter product resulting from radioactive decay can potentially react chemically with the surrounding solid matrix. This reaction may depend on the properties of the daughter product and the matrix material. It is important to consider these interactions when assessing the behavior of radioactive materials in a solid matrix.

Let's step through the half-life of radon to see how it works. Radon-222 starts at full strength. In four days (its half-life), it is at half strength. In four more days, it is again at half strength (of the half strength) for a total of 1/4 strength. In four more days, it is again half the strength (of the 1/4 strength) for a total of 1/8 strength. In four more days, it is another half life weaker, for a total of 1/16 strength. In 16 days, this isotope of radon has just 1/16th the original radiation.

There is no such thing as a negative neutron. Neutrons are neutral particles found within the nucleus of an atom, carrying no charge.

Nuclear chemistry is the branch of chemistry that studies the chemical and physical properties of elements as influenced by changes in the structure of atomic nuclei. It involves processes such as radioactive decay, nuclear reactions, and the use of radioactive isotopes in various applications such as medicine, industry, and research.

The smallest piece of a chemical compound is a molecule. The smallest part of an element is an atom. The smallest part of an atom (meaning of the proton, neutron and electron, which are an atom's building blocks) is the electron. Beyond that, the quark is a fundamental building block of matter, and it makes up neutrons and protons. Quarks also explain the "particle zoo" seen before the Standard Model arose to gather the phenomenon under one theoretical umbrella.

The strong nuclear force acts on neutrons and proton in the nucleus to hold them together. This is also called binding energy, and it is about 100 times more powerful than the electromagnetic force, which would cause the protons to repel each other.

J.J. Thomson proposed that an atom consists of a mixture of positively charged protons and negatively charged electrons. In his model, the electrons can be thought of as tiny marbles suspended in a "pudding" made up of protons.

Niels Bohr found this model to be incorrect, and instead described the atom more accurately as a sort of planetary configuration. In his model, electrons orbit the nucleus which consists of the protons.

Bohr's model was backed up experimentally by Ernest Rutherford's work.

After 1.6 seconds, 0.6 g astatine-218 remains unchanged. This amount is reduced by half to 0.3 g at 3.2 seconds. It is halved again at 4.8 seconds to 0.15 g, and halved once more to 0.075 g unchanged after a total of 6.4 seconds.

If a body is at rest, it experiences no acceleration. From what frame of reference are you observing the object? You are in a closed elevator in freefall toward earth. You have a tennis ball with you, hanging freely and motionless in front of you (disregarding the drag from air). From your frame of reference it is motionless. I am observing you and the tennis ball from the earth's surface. From my frame of reference, you and the ball are accelerating at 9.8 meters per second per second. Neither of us is wrong. But it won't go so well for you and the ball unless I beam you out, which I surely do.

An electron is an elementary particle, and is one of the family of particles called leptons. The leptons are a family of the group called the fermions.

Technetium-97 has the shortest half-life of any naturally occurring element, with a half-life of about 4.2 million years. Artificially produced elements typically have even shorter half-lives, with some lasting only fractions of a second.