Few people are surprised by the fact that an asteroid, the size of Mt. Everest, could do a lot of damage when it hits the Earth. And it is not really surprising that such bodies are out there; every few years, there is a newspaper headline about a "near miss" in which an object misses the Earth by "only a few million miles." But why should an asteroid impact cause an explosion? It was made of rock, not dynamite. And why such a big explosion? But then, what is an explosion, after all?
An explosion occurs when a great deal of energy is "released" into a small volume in a very short period of time. It doesn't matter what the source of the energy is; it could be chemical (stored in food), or kinetic (the result of motion).
However, nuclear bombs are the most devastating of them all and can cause some serious damage in its surroundings The dominant effects of a nuclear weapon (the blast and thermal radiation) are the same physical damage mechanisms as conventional explosives, but the energy produced by a nuclear explosive is millions of times more per gram and the temperatures reached are in the tens of mega kelvins. Nuclear weapons are quite different from regular weapons because of the huge amount of explosive energy they can put out and the different kinds of effects they make, like high temperatures and nuclear radiation.
The devastating impact of the explosion does not stop after the initial blast, as with regular explosives. A cloud of nuclear radiation travels from the epicenter of the explosion, causing an impact to lifeforms even after the heat waves have ceased. The radiation can cause genetic mutation, radiation poisoning, and death. because of this harmful effects, during the cold war people were traumatized to live in a time period where atom bombs seemed to make the power of the country greater and unfortunately it wasnt a success