Specific activity several other biomedical applications. Specific activity Specific activity is the activity per quantity of a radionuclide and is a physical property of that radionuclide. Activity is a quantity related to radioactivity. The SI unit of activity is the becquerel (Bq), equal to one reciprocal second. The becquerel is defined as the number of radioactive transformations per second that occur in a particular radioactive isotope. Its related non-SI unit equivalent is the Curie (Ci) which is transformations per second. Since the probability of radioactive decay for a given radionuclide is a fixed physical quantity (with some slight exceptions, see changing decay
Orders of magnitude (mass) Orders of magnitude (mass) To help compare different orders of magnitude, the following lists describe various mass levels between 10 kg and 10 kg. The table below is based on the kilogram (kg), the base unit of mass in the International System of Units (SI). The kilogram is the only standard unit to include an SI prefix ("kilo-") as part of its name. The "gram" (10 kg) is an SI derived unit of mass. However, the "names" of all SI mass units are based on "gram", rather than on "kilogram"; thus 10 kg is a "megagram" (10 g), not a