BECQUERELSBecquerel is the SI unit of radioactivity. The Becquerel (Bq) is used to measure the activity of a radioactive sample. This is the average number of nuclei breaking per second. For example, iodine-128 decays by throwing out beta particles. If in a sample, 40 nuclei break every second and then 40 40 beta particles are thrown every second, then the activity is 40 Bq. Antoine Henri Becquerel was born in Paris on December 15, 1852, a member of a distinguished family of scholars. and scientific. The bacqeral is named after the one who received a noble prize with Marie Curie and Pierri Currie. CELCIUSCelcius or also known as centigrade was discovered by Swedish astronomer Anders Celcius (1701–1744). The unit was known until 1948 as "centigrade" from the Latin centum translated as "steps". From 1744 to 1954, 0°C was defined as the freezing point of water and 100°C as the boiling point of water. at a pressure of one standard atmosphere with mercury as the base of the thermometer. Later, the body of international standard units defined the kelvin (k) as the unit of temperature and not Celsius. Kelvin The kelvin is a unit of measurement for temperature. It is one of the seven base units of the International System of Units (SI) and has the unit symbol K. The Kelvin scale is an absolute thermodynamic temperature scale using o degrees as the point where all particles cease to vibrate or move. .Lord Kelvin was a Scottish mathematician and physicist who contributed to many branches of physics. He also calculated the age of the earth. He was born in Belfast in 1824. At the University of Glasgow he did important work on the mathematical analysis of electricity and the formulation of...... middle of paper ...... and was especially noted for his work on alternating current and wireless communication. He also invented the Tesla coil. The SI unit of magnetic flux is named after him. The tesla is the SI-derived unit of magnetic field intensity or magnetic flux density, commonly denoted by B. One tesla is equivalent to one weber per square meter, VOLT The volt is the derived unit of electric potential, of the electric potential difference and the electromotive force. A volt is defined as the difference in electrical potential between two points on a conducting wire when an electric current of one ampere dissipates one watt of power between those points. Alessandro Volta (February 18, 1745 – March 5, 1827) was an Italian physicist. who was known for inventing the battery. Volta is also known for its discoveries in electrostatics and meteorology. voltas.WATT battery design