bell pulse
41telephone — telephoner, n. /tel euh fohn /, n., v., telephoned, telephoning. n. 1. an apparatus, system, or process for transmission of sound or speech to a distant point, esp. by an electric device. v.t. 2. to speak to or summon (a person) by telephone. 3.… …
42Mathematics 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… …
43Laser — For other uses, see Laser (disambiguation). United States Air Force laser experiment …
44Telephone exchange — A telephone operator manually connecting calls with cord pairs at a telephone switchboard. In the field of telecommunications, a telephone exchange or telephone switch is a system of electronic components that connects telephone calls. A central… …
45Pulsar — Pour les articles homonymes, voir Pulsar (homonymie). Un pulsar est le nom donné à l objet astrophysique produisant un signal périodique, de période allant de l ordre de la milliseconde à quelques dizaines de secondes. Il est considéré comme… …
46Pulsars — Pulsar Pour les articles homonymes, voir Pulsar (homonymie). Un pulsar est le nom donné à une étoile à neutrons, tournant très rapidement sur elle même (période typique de l ordre de la seconde, voire beaucoup moins pour les pulsars milliseconde) …
47Jet pack — For other meanings see Jetpack (disambiguation). : The Martin Jetpack, despite its name, has no jets or rockets, but is a small helicopter, and is discussed as such. Jet pack, rocket belt, rocket pack, and similar names, are various types of… …
48P.U.L.S.E — Pink Floyd – Pulse Veröffentlichung alle Formate: 5. Juni 1995 außer DVD: 10. Juli 2006 Label EMI (Europa) Columbia Records (USA) Format(e) CD, LP, Cassette, VHS, Video CD, DVD Genre(s) Rock …
49History of radar — The history of radar starts with experiments by Heinrich Hertz in the late 19th century that showed that radio waves were reflected by metallic objects. This possibility was suggested in James Clerk Maxwell s seminal work on electromagnetism.… …
50Caller ID — (caller identification, CID), also called calling line identification (CLID) or calling number identification (CNID) or Calling Line Identification Presentation (CLIP), is a telephone service, available in analog and digital phone systems and… …
