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Glaser, Donald Arthur

(Encyclopedia)Glaser, Donald Arthur, 1926–2013, American physicist, b. Cleveland, Ph.D. California Institute of Technology, 1950. He was a professor at the Univ. of Michigan from 1950 to 1959, when he joined the ...

stun gun

(Encyclopedia)stun gun, hand-held electronic device that produces a high-voltage pulse that can immobilize a person for several minutes with no permanent damage in most cases. It is powered by ordinary batteries, w...

radioactive waste

(Encyclopedia)radioactive waste, material containing the unusable radioactive byproducts of the scientific, military, and industrial applications of nuclear energy. Since its radioactivity presents a serious health...

circuit breaker

(Encyclopedia)circuit breaker, electric device that, like a fuse, interrupts an electric current in a circuit when the current becomes too high. The advantage of a circuit breaker is that it can be reset after it h...

radio-frequency identification

(Encyclopedia)radio-frequency identification (RFID), a technology that uses radio waves to transmit data and uniquely identify an animal, person, or thing. An RFID system typically consists of a tag and a reader. T...

Cronin, James Watson

(Encyclopedia)Cronin, James Watson, 1931–2016, American nuclear physicist, b. Chicago, Ph.D. Univ. of Chicago, 1955. Cronin and co-researcher Val Logsdon Fitch were awarded the 1980 Nobel Prize in Physics for a 1...

seismology

(Encyclopedia)seismology sīzmŏlˈəjē, sīs– [key], scientific study of earthquakes and related phenomena, including the propagation of waves and shocks on or within the earth by natural or artificially genera...

motor, electric

(Encyclopedia)CE5 Motor: In the AC motor, current fed to the conducting loop of wire causes it to rotate in the magnetic field, thus turning the shaft on which the loop is mounted. In the DC motor, the direction...

battery, electric

(Encyclopedia)CE5 Lead storage cell: At the lead-dioxide electrode, electrons from the circuit combine with lead dioxide and sulfuric acid to form lead sulfate and water. At the spongy-lead electrode, lead react...

X-ray astronomy

(Encyclopedia)X-ray astronomy, study of celestial objects by means of the X rays they emit, in the wavelength range from 0.01 to 10 nanometers. X-ray astronomy dates to 1949 with the discovery that the sun emits X ...