What is radioactivity?What is radioactivity? Please explain in detail.
Radioactivity occurs when the nucleus of certain unstable atoms (with an atomic mass greater than 83) or certain isotopes (with an atomic mass less than 83) disintegrates. This process releases a stream of particles called radiation. The radiation penetrates or is absorbed into other materials. There are three type of particle streams (or rays) that are found in radiation:
1) Alpha: composed of helium nuclei; low absorption and penetration; capable of changing other element's nuclei
2) Beta: composed of electrons; high speed and penetration; low mass; capable of changing other element's nuclei
3) Gamma: electromagnetic rays; high energy; short wavelengths; high penetrating power; does not change other element's nuclei
We are constantly being exposed to a certain amount of radioactivity (i.e. sun's rays, cosmic rays, etc.) every day and all we can do is limit our exposure to it. Some radioactivity is life-threatening, however, and exposure to it should be prevented at all costs.