converted wave method
51Partial differential equation — A visualisation of a solution to the heat equation on a two dimensional plane In mathematics, partial differential equations (PDE) are a type of differential equation, i.e., a relation involving an unknown function (or functions) of several… …
52History 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.… …
53mathematics — /math euh mat iks/, n. 1. (used with a sing. v.) the systematic treatment of magnitude, relationships between figures and forms, and relations between quantities expressed symbolically. 2. (used with a sing. or pl. v.) mathematical procedures,… …
54motion picture, history of the — Introduction history of the medium from the 19th century to the present. Early years, 1830–1910 Origins The illusion of motion pictures is based on the optical phenomena known as persistence of vision and the phi phenomenon. The first …
55SHABBETAI ẒEVI — (1626–1676), the central figure of Shabbateanism, the messianic movement named after him. Background of the Movement Shabbateanism was the largest and most momentous messianic movement in Jewish history subsequent to the destruction of the Temple …
56Ship — A ship IPA|/ʃɪp/ audio|en us ship.ogg|Audio (US) is a large vessel that floats on water. Ships are generally distinguished from boats based on size. Ships may be found on lakes, seas, and rivers and they allow for a variety of activities, such as …
57Mechanical filter — Figure 1. A mechanical filter made by the Kokusai Electric Company intended for selecting the narrow 2 kHz bandwidth signals in SSB radio receivers. It operates at 455 kHz, a common IF for these receivers, and is dimensioned 45×15×15 mm ( …
58Radio transmitter design — In plate modulation systems the voltage delivered to the stage is changed. As the power output available is a function of the supply voltage, the output power is modulated. This can be done using a transformer to alter the anode (plate) voltage.… …
59Naval mine — Polish wz. 08/39 contact mine. The protuberances around the top of the mine, called Hertz horns, are part of the detonation mechanism …
60X-ray — [ 22 December 1895 and presented to Professor Ludwig Zehnder of the Physik Institut, University of Freiburg, on 1 January 1896. The dark oval on the third finger is a shadow produced by her ring. [cite book last = Kevles first =Bettyann Holtzmann …
