Physics1. a) radiation ~ Spontaneous decay or disintegration of an unstable atomic nucleus accompanied by the emission of radiation. b) nuclear energy ~ Energy released when atomic nuclei undergo a nuclear reaction such as spontaneous emission of radioactivity, nuclear fission or nuclear fusion. c) background radiation ~ relatively constant low-level radiation from environmental sources such as building materials, cosmic rays, and radionuclides ingested into the body. d) nuclear fission ~ atomic nuclear processes that involve the division of nuclei with the accompanying release of energy. e) nuclear fusion ~ Nuclear process by which several small nuclei are combined to form a larger one whose mass is slightly less than the sum of the small nuclei.2. Two types of nuclear reactions can produce nuclear energy. Nuclear fusion is a process in which two light nuclei combine to form a single, heavier nucleus. Nuclear fission is a process in which a heavy nucleus splits into two smaller nuclei.3. Alpha, beta and gamma radiation are produced during the decay of an unstable nucleus. Alpha particles are made up of 2 protons and 2 neutrons. This means that they have a charge of +2 and a mass of 4Alpha particles is relatively slow and heavy. have low penetrating power - you can stop them with just a sheet of paper. Because they have a large charge, alpha particles strongly ionize other atoms. Beta particles have a charge of minus 1 and a mass of about 1/2000th of a proton. This means that beta particles are the same as electrons. They are fast and light. Beta particles have average penetrating power: they are stopped by a sheet of aluminum or plastic such as Plexiglas. Beta particles ionize the atoms they pass through, but not as strongly as alpha particles. Gamma rays are waves, not particles. This means they have no mass or charge. Gamma rays have high penetrating power: you need a thick sheet of metal like lead or concrete to reduce them significantly. Gamma rays do not directly ionize other atoms, although they can cause Atoms to emit other particles which will then cause ionization.4. Advantages of using nuclear energy instead of energy produced by fossil fuels: The Earth has limited reserves of coal and oil. Nuclear power plants could still produce electricity even after the shortage of coal and oil. Nuclear power plants need less fuel than those burning fossil fuels. A ton of uranium produces more energy than several million tons of coal or several million barrels of oil.