Nuclear Physics (radioactivity, nuclear fission and fusion) - SS3 Physics Lesson Note

Nuclear physics is the study of the atomic nucleus, including its properties, structure, and interactions. It involves the study of the behaviour of subatomic particles, including protons and neutrons, and the energy and matter that they produce.

Radioactivity is a process in which unstable atomic nuclei decay into more stable forms, emitting radiation in the process. The three types of radiation emitted during radioactive decay are alpha particles, beta particles, and gamma rays. Alpha particles consist of two protons and two neutrons and are positively charged, while beta particles are electrons or positrons that are emitted during nuclear decay. Gamma rays are high-energy electromagnetic radiation that are emitted during radioactive decay.

Nuclear fission is a process in which the nucleus of an atom is split into two or more smaller nuclei, releasing a large amount of energy in the process. This process is used in nuclear power plants to produce energy by splitting the nuclei of uranium or plutonium isotopes.

Nuclear fusion is a process in which the nuclei of two or more atoms combine to form a single, more massive nucleus, releasing a large amount of energy in the process. This process is the basis for the energy produced by stars, including our own sun. Fusion reactions require extremely high temperatures and pressures to occur, which are difficult to create on Earth.

Nuclear physics plays a crucial role in many areas of science and technology, including nuclear power, nuclear medicine, and the study of the origin and evolution of the universe. It also has important applications in the development of new materials, such as radiation-resistant materials for use in nuclear power plants, and in the study of the fundamental building blocks of matter.