Am not aware of any accidental nuclear explosions. Anywhere. Ever.
yes
no!
It explodes.
first off, of course, a nuclear bomb is thousands of times stronger than a normal bomb. a nuclear bomb also carries radiation, energy that causes poisoning and cancer, while most normal bombs cant do that.
US, who else?
no
Hiroshima was nearly totally destroyed by the atom bomb.
1946 off by one year, 1945
Tthe last hydrogen bomb was set of 1991 under the Nevada desert.
That will depend on the size of the bomb, how far above ground it explodes, and how far away it is from you.
We won't know that for several years, if ever.
It did explode, but this was due to a surge in steam pressure which blew off the top of the reactor, it was not a nuclear explosion as in a nuclear weapon.