A nuclear weapon is any destructive force made from combining atoms, or splitting them. These things would be known as as nuclear fusion ( combining atoms) or nuclear fission (splitting them).An explosion from a nuclear weapon is so powerful because once a nucleus of hits an atom, that atom's nucleus goes flying and hits other atoms causing a massive chain reaction. These deadly weapons were deliberately used only twice in the history of warfare. Both were used in World War II on Japan. The first was known as the "Little Boy" and was dropped on the city of Hiroshima. The second was known as the "Fat Man" and was dropped on the city of Nagasaki.These weapons stopped the war and caused about 150,000 deaths together. Thes e days these weapons are only used for demonstration to see what they can do, and tests to see what formulas may cause them to be more powerful. These nuclear weapons created many deaths of people in current Japan which caused many of them to have many hates against Americans, but other than that, it had a good effect. The thing is that these bombs were so powerful that Japan agreed never to again be involved in war which is a good side to the use of the bombs. Which may have stopped many wars that could have been happening today. Only Few countries currently have nuclear weapons now, and others may have some but have not yet admitted to having these destructive forces.They're as the following: The United Sates, The United Kingdom, Soviet Union, Republic of China, India, Pakistan, and North Korea. Nuclear weapons were created by many physicists, but a main person that helped make it was Albert Einstein. When he proved the equation E = MC^2 ( energy equals mass times speed of light to the second power) he did not have a nuclear weapon in mind. He refused to offer any of his help to the military no matter how much they asked him.When the first bomb was tested, it had the chain reaction of atoms getting split. Albert quickly studied and noticed how this was happening, and so did many other physicists. They learned that they could stop the atoms by keeping them enclosed and keeping other nucleus' from splitting other atoms. Many people today are completely against the creation of nuclear weapons, but this is not the decision of the citizens of the world, and so they are continually being made. But not all people see nuclear weapons as horrible destructive forces, some see them as something to be used as a last resort in a war,and to possibly stop another World War. The explosion and force of a nuclear weapon is enough to say its too much to handle, but its more than that. It forms a mushroom formed cloud of smoke in the air and rains down black liquid which causes you to get types of skin cancer many years later. These things are not just cancer but can be other flesh eating viruses that eat away your flesh and tissue.
This was the second atomic bomb created, the Fat Man.
This was the first atomic bomb created, the Little Boy.