the nuclear reactor exploded
It would probably create a localized ozone hole.
it means that either a nuclear rocket or a nuclear lab has exploded letting out nuclear waste and radiation which means the city would have to be evacuated until they are out of the nuclear radation zone.
Since most of the energy we get from the Sun is the result of nuclear fusion, I guess that would mean that we would receive ALMOST NO energy from the Sun. We WOULD receive some energy as a result of the Sun contracting due to gravity, but that wouldn't last long.
Nuclear energy, which is a kind of potential energy.
'BOOM'
First and foremost, it is impossible for a nuclear power plant to explode. i.e. to go nuclear, because it is impossible for it to stay in prompt critical geometry long enough to consume the fuel for a runaway reaction to occur. Period. Not possible. Even if a terrorist organization infiltrated the facility and blew it up, that would be a chemical explosion, not a nuclear explosion. Yes, there would be release of radioactive materials to the environment, but it would not be a nuclear detonation as from a nuclear bomb. Get your heads straight around that. Its just not possible. The geometry is all wrong.
Because it is energy derived from the heat made by a (Hopefully) controlled nuclear reaction. The nuclear reaction involves the nucleus of Uranium 235 (or possibly Plutonium 239) fissioning or splitting which releases a large amount of energy, so it is a nuclear process, not a chemical one such as would occur between atoms or molecules.
Nuclear fusion.
No, a nuclear explosion on a nuclear power plant would not cause the explosion radius to increase. The explosion radius would be determined by the yield of the nuclear weapon itself, not by the presence of the power plant.
No nuclear energy, no nuclear weapons
Nuclear energy is typically converted into electricity through nuclear power plants. During the process, nuclear reactions occur, producing heat that is used to generate steam, which then drives turbines connected to generators to produce electricity. Other potential uses of nuclear energy include propulsion for submarines and spacecraft.