ASTRO 142 Lecture Notes - Lecture 4: Beta Particle, Strong Interaction, Pauli Exclusion Principle
Document Summary
Europeans believed the arisotelian view that earthly matter consisted of four elements: fire, earth, water and fire. Structure of matter is described by atomic theory. Rutherford developed a new model for the atom: consisted of tightly packed positive nucleus with orbiting electrons. Chemistry is understood in terms of electron orbitals. Ionized gas consists of positive charged ions and free electrons. Neutron is bigger than proton but has no electrical charge. Nuclei of radioactive isotopes are unstable and emit radiation of some form: alpha particles, beta particles, gamma rays. Half life is the time required for half of a sample of a radioactive element to decay. Nuclear fission is the splitting of atomic nuclei. Nuclear fusion is the combining of light nuclei into a heavier nucleus: occur at high temperatures and densities. Quantum mechanics is the physical laws that governs the behavior of the elementary particles and of nuclei and atoms.
