How does a Nuclear bomb work?

Question

What makes a nuclear bomb so powerful? What is happening when it goes off, and what effect does it have on humans that are around the blast?

Answer 1

when two elements that are unstable already are smashed together some electrons fly off causing a chain reaction. the amount of energy released by just one atom in this event is enough to move a grain of sand. this is an enormous amount of energy for something so small. anybody near the blast would of course be incinerated instantly.

Answer 2

what kind, there are 2 kinds.

fission bomb- in a fission bomb, there are generally 2 parts. one shaped like a bullet, and the other like a partial sphere with a bullet hole cut into it. the parts are generally made out of uranium 235, or plutonium. when they impact, some atoms split into 2 smaller atoms. in the process, they emit 3 neutrons. those 3 neutrons impact other nuclei, cause them to be unstable, and they split in the same process. so you go from one atom splitting to 3, to 9, to 27 etc etc, and you get a chain reaction. and heres where the energy comes in. in nuclear chemistry, there is a term called binding energy. see, a nucleus of an atom has either more or less mass than the individual protons and neutrons that go into making it. with heavy elements like uranium and plutonium, the nucleus has more mass than its parts. so when it splits, it gives off some of that mass as energy in the form of a gamma ray.

there is another, much much more powerful type of bomb. a thermonuclear bomb. these are much more complicated.

a light element (i would think deuterium and tritium, but i think they used lithium) is surrounded by a small fission charge. that fission charge is ignited (i believe in the same way is described above) and it compresses the main fuel for the bomb. a thermonuclear bomb works of thermonuclear fusion. for light elements, it is the opposite of what i described above. the nucleus of an atom is lighter than its parts. so the fuel is compressed, and atoms fuse together to form heavier ones. in the process, mass is lost in the form of gamma rays.

thermonuclear bombs are much, much more powerful. an average fission bomb could wipe out most of a decent sized city. impressive for the 40's, but not too impressive today. i cant remember who said it, but some famous scientist or politician said "atomic bombs destroy cities, thermonuclear bombs destroy countries." thats a slight exaggeration of course, but not by much. the largest bomb ever built and exploded was called the tsar bomba, and it was built by russia. it had a yield of 50 megatons of TNT. the biggest the united states ever exploded was 15 megatons, and that was by accident. it was supposed to be 5 megatons. the bomb was so massively powerful that anyone without 100 km of it would have received 3rd degree burns covering their body. the shock wave from the bomb was felt on its 3rd pass around the earth. it broke windows in finland. thats amazing and terrifying at the same time.

Answer 3

Nukes work two ways: fission and fusion.  In a fission weapon, atoms are split into lighter elements.  Each split releases a bit of energy based on the famous E = mc^2.  All that blast and radiation we see in a nuke explosion comes from a very large number of atoms splitting at once due to something called a chain reaction.

A chain reaction is simply where one atom splits into two parts and these two parts split two more atoms and the resulting four parts split four more atoms...and so on.  Each series of splits is called a generation.  Roughly 2^23 = 8.3 million atoms will split after 23 generations of splitting.  That grows to 16.6 million atoms after the 24th generation and so on.  As you can see, the number of splitting atoms gets very big, very fast.  Eventually, a lot of energy is released before the physics package of the weapon is totally destroyed.

A fusion weapon works pretty much the same way...only in reverse.  Instead of making lighter elements out of heavier ones, fusion makes heavier elements out of lighter ones.  Atoms are brought together (fused) under tremendous heat and pressure.  Again, each generation of fusing creates more and more energy.  In fact, fusion weapons are capable of creating more energy than fission weapons.

Lethality is achieved by blast, prompt radiation, and fall out.  A tyypical strategic (fusion) weapon will have a blast lethal radius in the 3 to 5 mile range.  Tactial weapons (fission) are typically far lesser, not exceeding 1 mile radius.

Prompt radiation, heat and beta, has a lethal radius typically just slightly greater than the blast radius.  So very few casualties come from prompt radiation when compared with the blast results.  That is, chances are higher on being blown to bits than to burn to death...although both are possible.

Fall out occurs when a blast sucks up soil and stuff from the ground, vaporizes it, and the radioactive particles from that vapor fall eventually back to the ground.  Blasts need not have fall out if they are exploded high enough off ground level that very little is sucked up by the explosion.  On the other hand, blasts on or near the ground can have a lot of fall out.

Fall out lethality footprints (the pattern over the ground) generally follow the prevailing winds.  Which means, fall out will generally (not always) go west to east, which is the general direction of wind.  Depending on the size of the weapons and where they are exploded, a lethal fall out footprint can be hundreds of miles long and 50 miles wide.  And to a point, some radioactive particulates can be so fine they will be carried around thw world in the Stratosphere before they settle back to Earth.

Of all the kill mechanisms, radioactive fallout is probably the worst.  This follows because of the large areas it can cover and because the radioactivity can last for years.

Answer 4

see    http://en.wikipedia.org/wiki/Nuclear_bom...

Answer 5

When the core of atom explodes a large amount of energy release this energy can destroy almost everything in the radius of this explode, first when a nuclear bomb explode it works like another bombs, it destroys everything around that area then it burns everything and then the deadly rain begins to fall this rain is toxic and then for many years that area will remains toxicated. There is a way to avoid it's first exploding wave, when the nuclear bomb explode if you are so close you can see a white light in the sky you must quickly turn around and lie on the ground and cover your head with your hands but it won't save anyone because it's next waves will destroy everything.

Answer 6

A nuclear bomb uses a nuclear reaction to generate energy (heat and radiated particles).

There are two types of nuclear reactions, fission and fusion.

Fission Bombs

To create the chain reaction that will end up in the explosion of the bomb it is necessary to reach a supercritical mass. The nuclear fuel needs to be maintained in sub-critical state until the detonation time. The earliest bombs reached the supercritical mass by firing two charges of uranium at one another in a small chamber. In updated designs, a heavy core is surrounded by high-explosive changes designed to compress the core upon detonation, compression is the second way to achieve the supercritical state.

Limitations of Fission Bombs: The efficiency of fission bombs is low even in the best designs (about 25%). They are very heavy and use elements difficult to produce or store. Being the basic element instable in nature, manipulation is dangerous making the whole process very expensive.

For historical purposes we are going to go over three versions of fission bombs: little boy (used in Hiroshima), fat man (used in Nagasaki) and a modern version of fission bomb.

Fusion bombs

Fusion bombs use light materials: deuterium and tritium (both isotopes of hydrogen), as fuels. The process of fusion is safer and cleaner, but it can only be achieved at extremely high temperatures and pressures. This fact is responsible of calling them thermonuclear bombs. All model of fusion bombs so far use fission as part of the process, a pure fusion bomb has not been achieved yet.

There are two types of bombs that use fusion:

Boosted Fusion Bomb

Teller-Uman Design

From them, only the second uses fusion as the main process and it is the one called thermonuclear. The information about fusion bombs has not been completely declassified, but it is known enough to have a fair idea of how the original model works.