extremely high frequencies
21radiation — radiational, adj. /ray dee ay sheuhn/, n. 1. Physics. a. the process in which energy is emitted as particles or waves. b. the complete process in which energy is emitted by one body, transmitted through an intervening medium or space, and… …
22Mathematics and Physical Sciences — ▪ 2003 Introduction Mathematics Mathematics in 2002 was marked by two discoveries in number theory. The first may have practical implications; the second satisfied a 150 year old curiosity. Computer scientist Manindra Agrawal of the… …
23Laser — For other uses, see Laser (disambiguation). United States Air Force laser experiment …
24Capacitor — This article is about the electronic component. For the physical phenomenon, see capacitance. For an overview of various kinds of capacitors, see types of capacitor. Capacitor Modern capacitors, by a cm ruler Type Passive …
25Valve RF amplifier — A valve RF amplifier (UK and Aus.) or tube amplifier (U.S.), is a device for electrically amplifying the power of an electrical , typically (but not exclusively) radio frequency signals.Low to medium power valve amplifiers for frequencies below… …
26electronics — /i lek tron iks, ee lek /, n. (used with a sing. v.) the science dealing with the development and application of devices and systems involving the flow of electrons in a vacuum, in gaseous media, and in semiconductors. [1905 10; see ELECTRONIC,… …
27plasma — plasmatic /plaz mat ik/, plasmic, adj. /plaz meuh/, n. 1. Anat., Physiol. the liquid part of blood or lymph, as distinguished from the suspended elements. 2. Cell Biol. cytoplasm. 3. whey. 4. a green, faintly translucent chalcedony. 5. Physics. a …
28eye, human — ▪ anatomy Introduction specialized sense organ capable of receiving visual images, which are then carried to the brain. Anatomy of the visual apparatus Structures auxiliary to the eye The orbit The eye is protected from mechanical injury… …
29electron tube — an electronic device that consists, typically, of a sealed glass bulb containing two or more electrodes: used to generate, amplify, and rectify electric oscillations and alternating currents. Also called electronic tube. Cf. gas tube, vacuum tube …
30Vacuum tube — This article is about the electronic device. For experiments in an evacuated pipe, see free fall. For the transport system, see pneumatic tube. Modern vacuum tubes, mostly miniature style In electronics, a vacuum tube, electron tube (in North… …
