If a nuclear explosion renders the area uninhabitable for a half life of 2,500 years?

Then why are Hiroshima and Nagasaki thriving metropolitan areas?If a nuclear explosion renders the area uninhabitable for a half life of 2,500 years?
Half-life is not a measure of how long it takes for an area to become clean after exposure to radiation. It is the amount of time that it takes for a given sample of a radioactive element to decay to half its original mass.


Here's how it works: what makes radioactive elements radioactive is that their nuclei (the centre of the atom) are so large that they have difficulty staying together. Eventually, the nucleus (singlular of nuclei) of a radioactive element breaks up, or decays. When this happens, several protons and neutrons (the particles that make up the nucleus) go flying off at arond the speed of light - these are what make up the radiation. What's left over is an atom with fewer protons. Since the number of protons in the nucleus is what determines the type of atom, once a radioactive atom decays (gives off protons) it becomes an atom of a different (lighter) element, like lead. Half-life is the length of time it takes for half of any sample to decay in this manner.





So if it takes so long to decay, how are people living in Hiroshima today? Because you don't have to wait for it all to decay for the radiation to go away. The residual radiation is caused mostly by tiny particles of leftover radioactive material from the bomb. This radioactive dust lingers behind, continually emitting radiation. However, given time and clean-up efforts, the radioactive materials can be largely removed and life can resume.





Don't let that make you think that nuclear war wouldn't be the end of the world. WWII saw 2 little atomic bombs over the course of several days. A modern nuclear war would involve hundreds or thousands of nuclear weapons detonating around the globe over the course of a few hours, each more powerful than the 2 dropped on Japan.If a nuclear explosion renders the area uninhabitable for a half life of 2,500 years?
Those were tiny bombs (compared to today's), and were fission, not fusion (H-bomb).


The long lived components are dispersed on the surface, and also by water and wind.


Cleanup is posible, but only feasible when the affected area is rather small, as is the case with both of those cities.
It was an atomic bomb, not a nuclear bomb.





The Atomic bomb uses some of the same processes but is not as strong as a Hydrogen bomb ';thermonuclear'; warhead.





With an atomic bomb like what went off in Hiroshima/Nagasaki some radioactive products are borne into the upper atmosphere as dust or gas and may subsequently be deposited partially decayed as radioactive fallout far from the site of the explosion. The bomb dropped on Aug. 6, 1945, was an atomic bomb, uses fission, on the city of Hiroshima and had an estimated equivalent explosive force of 12,500 tons of TNT.





A hydrogen bomb, nuclear warhead uses fusion.





hydrogen bomb or H-bomb,weapon deriving a large portion of its energy from the nuclear fusion of hydrogen isotopes. In an atomic bomb, uranium or plutonium is split into lighter elements that together weigh less than the original atoms, the remainder of the mass appearing as energy. Unlike this fission bomb, the hydrogen bomb functions by the fusion, or joining together, of lighter elements into heavier elements. The end product again weighs less than its components, the difference once more appearing as energy. Because extremely high temperatures are required in order to initiate fusion reactions, the hydrogen bomb is also known as a thermonuclear bomb.
Someone is lying, aren't they.