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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...

Drude, Paul Karl Ludwig

(Encyclopedia)Drude, Paul Karl Ludwig poul kärl lo͝otˈvĭkh dro͞oˈdə [key], 1863–1906, German physicist. Drude first experimented with the physical determinants of optical constants, measuring the optical c...

endless screw

(Encyclopedia)endless screw, screw fixed so that it cannot move longitudinally as it rotates. Thus, instead of the usual action in which a screw advances itself through a medium as it turns, the screw remains stati...

Fermi-Dirac statistics

(Encyclopedia)Fermi-Dirac statistics, class of statistics that applies to particles called fermions. Fermions have half-integral values of the quantum mechanical property called spin and are “antisocial” in the...

joinery

(Encyclopedia)joinery, craft of assembling exposed woodwork in the interiors of buildings. Where carpentry refers to the rougher, simpler, and primarily structural elements of wood assembling, joinery has to do wit...

bionics

(Encyclopedia)bionics, the study of living systems with the intention of applying their principles to the design of engineering systems. Drawing on interdisciplinary research in the mechanical and life sciences, bi...

Mayer, Julius Robert von

(Encyclopedia)Mayer, Julius Robert von, 1814–78, German physician and physicist, studied medicine at Tübingen, Munich, and Paris. From a consideration of the generation of animal heat, he was led to determine th...

amplifier

(Encyclopedia)amplifier, device that accepts a varying input signal and produces an output signal that varies in the same way as the input but has a larger amplitude. The input signal may be a current, a voltage, a...

printer

(Encyclopedia)printer, device that reproduces text, images, or other data from a computer, digital camera, smartphone, or the like on paper or another medium. Impact printers, which mostly have been superseded by i...

vacuum cleaner

(Encyclopedia)vacuum cleaner, mechanical device using a draft of air to remove dust, loose dirt, or other particulate matter from dry surfaces. It is especially useful on highly textured surfaces, such as carpets a...