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Hertz, Heinrich Rudolf

(Encyclopedia)Hertz, Heinrich Rudolf hĕrts [key], 1857–94, German physicist. He confirmed J. C. Maxwell's electromagnetic theory and in the course of experiments (1886–89) produced and studied electromagnetic...

transducer

(Encyclopedia)transducer, device that accepts an input of energy in one form and produces an output of energy in some other form, with a known, fixed relationship between the input and output. One widely used class...

blanket

(Encyclopedia)blanket, sheet, usually of heavy woolen, or partly woolen, cloth, for use as a shawl, bed covering, or horse covering. The blanketmaking of primitive people is one of the finest remaining examples of ...

buoy

(Encyclopedia)buoy boi, bo͞oˈē [key], float anchored in navigable waters to mark channels and indicate dangers to navigation (isolated rocks, mine fields, cables, and the like). The shape, color, number, and mar...

galvanometer

(Encyclopedia)CE5 Galvanometer galvanometer gălˌvənŏmˈətər [key], instrument used to determine the presence, direction, and strength of an electric current in a conductor. All galvanometers are based upo...

electrodynamics

(Encyclopedia)electrodynamics, study of phenomena associated with charged bodies in motion and varying electric and magnetic fields (see charge; electricity); since a moving charge produces a magnetic field, electr...

electrolysis, cosmetic

(Encyclopedia)electrolysis, cosmetic, method of permanently removing superfluous or unwanted hair. A fine needle is inserted into the hair follicle; the application of an electric current through the needle destroy...

platinite

(Encyclopedia)platinite, alloy that is 46% nickel and 54% iron. It is used in the manufacture of electric lightbulbs because its coefficient of expansion, i.e., the rate at which its volume increases with temperatu...

Windham

(Encyclopedia)Windham, town (1990 pop. 22,039), Windham co., E Conn.; inc. 1692. It includes the industrial city of Willimantic where rubber, radio and electric parts, machinery, steel, and insulation are manufactu...

Derby, city, United States

(Encyclopedia)Derby dûrˈbē [key]. <1> city (2020 pop. 12,325), New Haven co., SW Conn., at the con...