From which height the effect of nuclear bomb will be Greater? Well I was wondering like during war some of them drop nuclear bomb on ground and then it explode and we see a huge blast which causes so much of destruction but my question is that is it possible that if someone explode that nuclear bomb with few heights above the ground and it may cause greater effect rather than hitting it on the ground?
In simple from which height someone has to explode that nuclear bomb to get more effect.
 A: If a nuclear bomb explodes very near the ground, the fallout is increased, as the bomb irradiates the surrounding dirt, however, the blast radius is decreased.
On the other hand, if the bomb is detonated a reasonable distance above ground, then the fallout is greatly decreased, and the blast radius is increased. A bonus is the "double shockwave" AKA "Mach Stem Formation" effect, in which a second shockwave is created by the blast wave reflecting off the ground below the bomb.
In the case of an extremely high altitude detonation, damage to structures is minimal, however, an EMP (electromagnetic pulse) is created, which may damage unprotected electronic equipment. The strength of the pulse depends on the earth's magnetic field in the area.
A: A nuclear weapon doesn't really "explode."  OK, I know that there are actual explosives used in the triggering of it, but Mostly it just gets really hot really fast.  Virtually all of the blast from a nuclear explosion is the result of the large volume of air that expands when it is suddenly heated by radiation from the bomb.
If the bomb goes off on the ground, some of that radiation will be absorbed by the ground and by nearby structures.  But, if it goes off a few hundred to a few thousand feet above ground, then most of the radiation will be absorbed by air, and the blast will be more powerful.
