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electrochemistry

(Encyclopedia)electrochemistry, science dealing with the relationship between electricity and chemical changes. Of principal interest are the reactions that take place between electrodes and the electrolytes in ele...

capacitor

(Encyclopedia)capacitor or condenser, device for the storage of electric charge. Simple capacitors consist of two plates made of an electrically conducting material (e.g., a metal) and separated by a nonconducting ...

Castle Clinton National Monument

(Encyclopedia)Castle Clinton National Monument: see Battery, the. ...

Edison, Thomas Alva

(Encyclopedia)Edison, Thomas Alva, 1847–1931, American inventor, b. Milan, Ohio. A genius in the practical application of scientific principles, Edison was one of the greatest and most productive inventors of his...

electricity

(Encyclopedia)CE5 Electrical and radio symbols electricity, class of phenomena arising from the existence of charge. The basic unit of charge is that on the proton or electron—the proton's charge is designate...

locomotive

(Encyclopedia)locomotive, vehicle used to pull a train of unpowered railroad cars. Richard Trevithick, a British engineer and inventor, built and operated (1803–4) the first successful steam engine locomotive f...

bicycle

(Encyclopedia)bicycle, light, two-wheeled vehicle driven by pedals. The name velocipede is often given to early forms of the bicycle and to its predecessor, the dandy horse, a two-wheeled vehicle moved by the thrus...

mayhem

(Encyclopedia)mayhem māˈhĕm, māˈəm [key], in common law, the crime of willfully injuring a person so as to diminish his or her capacity for self-defense. Cutting off an arm or leg would thus be mayhem, while ...

heart, artificial

(Encyclopedia)heart, artificial, external or surgically implanted mechanical device designed to replace a patient's diseased heart. The first one used on a human being, the Jarvik-7, was implanted (1982) in Barney ...

photoelectric cell

(Encyclopedia)CE5 Photoelectric cell: Light causes a photosensitive surface to emit electrons, which flow as current to the positive terminal. A galvanometer measures the current and thus indicates light intensi...