## Conceptual Physics (12th Edition)

Hi Grandma, You know that I'm a real fan of nuclear power, which I think has gotten a bad rap in the press. One type of nuclear power plant relies on fission, where we split a heavy atom, usually uranium, into lighter fragments. The "lost mass" shows up as energy, in the amount predicted by $E = mc^{2}$. Three advantages of fission power are plentiful electricity, the savings of fossil fuels to be harvested for organic molecules or other materials, and the lack of atmospheric pollution. Four drawbacks of fission power are the problem of waste storage, the danger of nuclear materials falling into the wrong hands and subsequent weapons development, the low-level release of radioactivity into the air and groundwater, and the risk of a catastrophic accident. For me, the positives outweigh the negatives. It turns out that both uranium-235 and plutonium-239 are fissionable. It may be a pipe dream, but if the countries of the world would dismantle their nuclear warheads, the plutonium in them could power so many of our fission plants that we could probably stop mining uranium. Today's nuclear power reactors work on fission. Another type of proposed nuclear power is fusion, where light atoms, usually hydrogen, fuse into a heavier atom whose mass is less than the sum of the initial masses. The "lost mass" shows up as energy, in the amount predicted by $E = mc^{2}$.