Columbia Encyclopedia

(Encyclopedia) momentum mōmĕnˈtəm [key], in mechanics, the quantity of motion of a body, specifically the product of the mass of the body and its velocity. Momentum is a vector quantity; i.e., it has both a magn...

(Encyclopedia) Starr, Kenneth Winston, 1946–2022, American public official, b. Vernon, Tex., grad. George Washington Univ. (B.A., 1968), Brown (M.A., 1969), Duke (J....

(Encyclopedia) diffraction, bending of waves around the edge of an obstacle. When light strikes an opaque body, for instance, a shadow forms on the side of the body that is shielded from the light source. Ordinarily...

(Encyclopedia) communicable diseases, illnesses caused by microorganisms and transmitted from an infected person or animal to another person or animal. Some diseases are passed on by direct or indirect contact with ...

(Encyclopedia) blood bank, site or mobile unit for collecting, processing, typing, and storing whole blood, blood plasma and other blood constituents. Most hospitals maintain their own blood reserves, and the Americ...

(Encyclopedia) boiling point, temperature at which a substance changes its state from liquid to gas. A stricter definition of boiling point is the temperature at which the liquid and vapor (gas) phases of a substanc...

(Encyclopedia) Flynn, Michael Thomas, 1958–, U.S. military officer and government official, b. Middletown, R.I., Univ. of Rhode Island (B.S., 1981). Commissioned as ...

(Encyclopedia) herpes simplex hûrˈpēz [key], an acute viral infection of the skin characterized by one or more painful, itching blisters filled with clear fluid. It is caused by either of two herpes simplex virus...

(Encyclopedia) key. 1 In music, term used to indicate the scale from which the tonal material of a given composition is derived. To say, for example, that a composition is in the key of C major means that it uses as...

(Encyclopedia) waters, territorial, all waters within the jurisdiction, recognized in international law, of a country. Certain waters by their situation are controlled by one nation; these include wholly enclosed in...