Gravity if forming the clouds from the atomic bomb.
a nuclear explosion
uncontrolled nuclear fission and/or fusion.
This question makes no sense as an atomic bomb is a nuclear bomb and vice versa. They are the same thing.
This question could be easily misconstrued. While atomic and nuclear explosion mean the same thing, and all atomic bombs are nuclear bombs, not all nuclear bombs are atomic bombs. The more powerful nuclear bombs are hydrogen bombs, and there is a very important fundamental difference between the two. ============================================================== A bomb is fission - the splitting of an atom H bomb is fusion - the joining together of atoms (and much more powerfull)
The nuclear fusion uses Hydrogen to produce Helium. The fusion also releases a lot of energy, which is what causes the explosion.
No
fallout, a mixture of debris picked up by the updraft in the mushroom cloud and condensed vaporized bomb materials.
If you are referring to the blast of a nuclear bomb, you could easily lose your vision.
Any explosion on the ground makes a mushroom cloud, even small grenades. This is because of the physics of the explosion. The high pressure pushes out rapidly, making a low pressure zone in the middle of the explosion. Air rushes back in to fill this area, making the smaller "pinched" area that looks like the mushroom stalk.
When an atomic bomb explodes it forms a mushroom cloud, the explosion gives off EMP or Electro Magnetic Pulse, the explosion is huge and can destroy so much for miles, and the explosion gives off huge amounts of radiation so if you survive the explosion you can suffer or die from the radiation after the bomb blew up.
a nuclear explosion
Noboby can survive a nuclear bomb if he is within explosion distance.
a radioactive fallout cloud
Any atmospheric, surface, or shallow subsurface burst. If it is too high to entrain dirt or water then the cloud is composed entirely of material from the bomb itself.
Go and find out your self.
Big
Every explosion happening in an atmosphere makes a mushroom cloud; whether the explosion is a tiny firecracker, a hand grenade, a conventional bomb (e.g. the three explosions shown in the photo above), an atomic bomb, a hydrogen bomb, an explosive volcanic eruption, a meteor exploding in midair due to thermal stresses (e.g. comet Shoemaker-Levy 9 at Jupiter), a meteor impact making a crater, etc. How visible the mushroom cloud is and how long it persists depends on the yield of the explosion (how big it was in terms of energy released). The mushroom shape is simply an effect of buoyancy: hot gasses produced by the explosion are less dense than the surrounding air so they rise with the cap of the mushroom being a toroidal vortex (similar to a smoke ring).Similar clouds can be observed in the smoke above large fires and water vapor above cooling towers, but usually missing a well defined cap.Underground salt domes (that contain petroleum and natural gas) result from the same density phenomenon, with less dense salt rising through more dense rock. However here in most cases only the cap remains without the stem.