Columbia Encyclopedia

Search results

500 results found

electrode

(Encyclopedia)electrode, terminal through which electric current passes between metallic and nonmetallic parts of an electric circuit. In most familiar circuits current is carried by metallic conductors, but in som...

Boltzmann, Ludwig

(Encyclopedia)Boltzmann, Ludwig lo͝otˈvĭkh bôltsˈmän [key], 1844–1906, Austrian physicist, b. Vienna, educated at Univ. of Vienna. He began teaching (1869) at Graz Univ. In 1873 he became mathematics profes...

pole, in electricity and magnetism

(Encyclopedia)pole, in electricity and magnetism, point where electric or magnetic force appears to be concentrated. A single electric charge located at a point is sometimes referred to as an electric monopole. An ...

field, in physics

(Encyclopedia)field, in physics, region throughout which a force may be exerted; examples are the gravitational, electric, and magnetic fields that surround, respectively, masses, electric charges, and magnets. The...

kinetic-molecular theory of gases

(Encyclopedia)kinetic-molecular theory of gases, physical theory that explains the behavior of gases on the basis of the following assumptions: (1) Any gas is composed of a very large number of very tiny particles ...

Sauvage, Jean-Pierre

(Encyclopedia)Sauvage, Jean-Pierre, 1944–, French chemist, Ph.D. Univ. of Strasbourg, 1971. He has spent his entire career as a researcher at the National Center for Scientific Research and a professor at the Uni...

hot spring

(Encyclopedia)hot spring, natural discharge of groundwater having an elevated temperature. Most hot springs result from the emergence of groundwater that has passed through or near recently formed, hot, igneous roc...

entropy

(Encyclopedia)entropy ĕnˈtrəpē [key], quantity specifying the amount of disorder or randomness in a system bearing energy or information. Originally defined in thermodynamics in terms of heat and temperature, e...

Nuclear Regulatory Commission

(Encyclopedia)Nuclear Regulatory Commission (NRC), an independent U.S. government commission, created by the Energy Reorganization Act of 1974 and charged with licensing and regulating civilian use of nuclear energ...

low-temperature physics

(Encyclopedia)low-temperature physics, science concerned with the production and maintenance of temperatures much below normal, down to almost absolute zero, and with various phenomena that occur only at such tempe...