Final answer:
Natural radiation refers to radiation originating from natural sources such as the sun, cosmic rays, and radioactive elements in the earth's crust. The primary components include cosmic rays and terrestrial sources such as radon gas, uranium and thorium. Background radiation encompasses these natural sources and varies by location.
Step-by-step explanation:
Natural radiation refers to b) radiation originating from natural sources like the sun and rocks, not to radiation produced by human activities. Sources of natural radiation include cosmic rays, soil, and building materials that contain naturally occurring radioactive elements such as radon gas. Additionally, there are internal sources of natural radiation, such as the radioactive elements incorporated into the human body.
Background Radiation
Background radiation is the natural radiation we are exposed to every day from our environment. This includes radiation from cosmic rays, which are high-energy particles originating from outer space, and terrestrial radiation from radioactive materials in the earth's crust, such as uranium, thorium, and radium, which can be found in certain rocks and soil. Human exposure to natural radiation can vary based on location due to different concentrations of radioactive materials in the geology of an area.
Sources included in Background Radiation
Every one of us absorbs a certain amount of background radiation in our daily lives, from both natural and human-made sources. The natural sources are predominant in most cases. For instance, radon gas, emanating from the natural decay of uranium and thorium isotopes in the soil, contributes significantly to background radiation exposure. Consumable items like foods can also contain natural radionuclides like potassium-40 and carbon-14.