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Tin Can Telephone
A tin can phone is a type of Acoustics, acoustic (non-electrical) speech-transmitting device made up of two tin cans, paper cups or similarly shaped items attached to either end of a taut string or wire. It is a particular case of mechanical telephony, where sound (i.e., vibrations in the air) is converted into vibrations along a Transmission medium, liquid or solid medium. These vibrations are transmitted through the medium (string) and then converted back to sound. History Before the invention of the telephone, electromagnetic telephone, there were mechanical acoustic devices for transmitting spoken words and music over a greater distance, faster than the speed of sound in air. The very earliest mechanical telephones were based on transmission through Speaking tube, pipes or other Transmission medium, physical media, and among the very earliest experiments were those conducted by the British physicist and polymath Robert Hooke from 1664 to 1685.McVeigh, Daniel PAn Early Histor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fig 7 Le Telephone By T Du Moncel Paris 1880 (Large)
The fig is the edible fruit of ''Ficus carica'', a species of tree or shrub in the flowering plant family Moraceae, Native plant, native to the Mediterranean Basin, Mediterranean region, together with western and southern Asia. It has been cultivated since ancient times and is now widely grown throughout the world.''The Fig: its History, Culture, and Curing'', Gustavus A. Eisen, Washington, Govt. print. off., 1901 ''Ficus carica'' is the type species of the genus ''Ficus'', which comprises over 800 tropical and subtropical plant species. A fig plant is a deciduous tree or large shrub, growing up to tall, with smooth white bark. Its large leaves have three to five deep lobes. Its fruit (referred to as syconium, a type of is tear-shaped, long, with a green fruit that may ripen toward purple or brown, and sweet soft reddish flesh containing numerous crunchy seeds. The milky sap of the green parts is an Irritant (biology), irritant to human skin. In the Northern hemisphere, fres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrographia
''Micrographia: or Some Physiological Descriptions of Minute Bodies Made by Magnifying Glasses. With Observations and Inquiries Thereupon'' is a historically significant book by Robert Hooke about his observations through various lenses. It was the first book to include illustrations of insects and plants as seen through microscopes. Published in January 1665, the first major publication of the Royal Society, it became the first scientific best-seller, inspiring a wide public interest in the new science of microscopy. The book originated the biological term '' cell''. Observations Hooke most famously describes a fly's eye and a plant cell (where he coined that term because plant cells, which are walled, reminded him of the cells of a monastery"... I could exceedingly plainly perceive it to be all perforated and porous, much like a Honey-comb, but that the pores of it were not regular .these pores, or cells, .were indeed the first microscopical pores I ever saw, and perhap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sound-powered Telephone
A sound-powered telephone is a communication device that allows users to talk to each other with the use of a handset, similar to a conventional telephone, but without the use of external power. This technology has been used since at least 1944 for both routine and emergency communication on ships to allow communication between key locations on a vessel if power is unavailable. A sound-powered phone circuit can have two or more stations on the same circuit. The circuit is always live, thus a user begins speaking rather than dialing another station. Sound-powered telephones are not normally connected to a telephone exchange. Operation The microphone transducer converts sound pressure from a user's voice into an electric current, which is then converted back to sound by a transducer at the receiver nodes. The most significant distinction between ordinary telephones and sound-powered telephones is in the operation of the microphone. Since the microphones used in most telep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of The Telephone
This history of the telephone chronicles the development of the electrical telephone, and includes a brief overview of its predecessors. The first telephone patent was granted to Alexander Graham Bell in 1876. Mechanical acoustic devices Before the invention of electromagnetic telephones, mechanical acoustic devices existed for transmitting speech and music over a greater distance. This distance was greater than that of normal direct speech. The earliest mechanical telephones were based on sound transmission through pipes or other physical media. The acoustic tin can telephone, or "lovers' phone", has been known for centuries. It connects two diaphragms with a taut string or wire, which transmits sound by mechanical vibrations from one to the other along the wire (and not by a modulated electric current). The classic example is the children's toy made by connecting the bottoms of two paper cups, metal cans, or plastic bottles with tautly held string. Some of the earl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tension (physics)
Tension is the pulling or stretching force transmitted axially along an object such as a string, rope, chain, rod, truss member, or other object, so as to stretch or pull apart the object. In terms of force, it is the opposite of ''compression''. Tension might also be described as the action-reaction pair of forces acting at each end of an object. At the atomic level, when atoms or molecules are pulled apart from each other and gain potential energy with a restoring force still existing, the restoring force might create what is also called tension. Each end of a string or rod under such tension could pull on the object it is attached to, in order to restore the string/rod to its relaxed length. Tension (as a transmitted force, as an action-reaction pair of forces, or as a restoring force) is measured in newtons in the International System of Units (or pounds-force in Imperial units). The ends of a string or other object transmitting tension will exert forces on the objects ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanical Vibration
Vibration () is a mechanical phenomenon whereby oscillations occur about an equilibrium point. Vibration may be deterministic if the oscillations can be characterised precisely (e.g. the periodic motion of a pendulum), or random if the oscillations can only be analysed statistically (e.g. the movement of a tire on a gravel road). Vibration can be desirable: for example, the motion of a tuning fork, the reed in a woodwind instrument or harmonica, a mobile phone, or the cone of a loudspeaker. In many cases, however, vibration is undesirable, wasting energy and creating unwanted sound. For example, the vibrational motions of engines, electric motors, or any mechanical device in operation are typically unwanted. Such vibrations could be caused by imbalances in the rotating parts, uneven friction, or the meshing of gear teeth. Careful designs usually minimize unwanted vibrations. The studies of sound and vibration are closely related (both fall under acoustics). Sound, or pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sound Wave
In physics, sound is a vibration that propagates as an acoustic wave through a transmission medium such as a gas, liquid or solid. In human physiology and psychology, sound is the ''reception'' of such waves and their ''perception'' by the brain. Only acoustic waves that have frequencies lying between about 20 Hz and 20 kHz, the audio frequency range, elicit an auditory percept in humans. In air at atmospheric pressure, these represent sound waves with wavelengths of to . Sound waves above 20 kHz are known as ultrasound and are not audible to humans. Sound waves below 20 Hz are known as infrasound. Different animal species have varying hearing ranges, allowing some to even hear ultrasounds. Definition Sound is defined as "(a) Oscillation in pressure, stress, particle displacement, particle velocity, etc., propagated in a medium with internal forces (e.g., elastic or viscous), or the superposition of such propagated oscillation. (b) Auditory sens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diaphragm (mechanical Device)
In mechanics, a diaphragm is a sheet of a semi-flexible material anchored at its periphery and most often round in shape. It serves either as a barrier between two chambers, moving slightly up into one chamber or down into the other depending on differences in pressure, or as a device that vibrates when certain frequencies are applied to it. A diaphragm pump uses a diaphragm to pump a fluid. A typical design is to have air on one side constantly vary in pressure, with fluid on the other side. The increase and decrease in volume caused by the action of the diaphragm alternately forces fluid out the chamber and draws more fluid in from its source. The action of the diaphragm is very similar to the action of a plunger with the exception that a diaphragm responds to changes in pressure rather than the mechanical force of the shaft. A diaphragm pressure tank is a tank which has pressurant sealed inside on one side of the diaphragm. It is favored in certain applications due to its h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
String With An Anchored Twist To Change Direction
String or strings may refer to: *String (structure), a long flexible structure made from threads twisted together, which is used to tie, bind, or hang other objects Arts, entertainment, and media Films * ''Strings'' (1991 film), a Canadian animated short * ''Strings'' (2004 film), a film directed by Anders Rønnow Klarlund * ''Strings'' (2011 film), an American dramatic thriller film * ''Strings'' (2012 film), a British film by Rob Savage * '' Bravetown'' (2015 film), an American drama film originally titled ''Strings'' * '' The String'' (2009), a French film Music Instruments * String (music), the flexible element that produces vibrations and sound in string instruments * String instrument, a musical instrument that produces sound through vibrating strings ** List of string instruments * String piano, a pianistic extended technique in which sound is produced by direct manipulation of the strings, rather than striking the piano's keys Types of groups * String band, musical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Graham Bell
Alexander Graham Bell (; born Alexander Bell; March 3, 1847 – August 2, 1922) was a Scottish-born Canadian Americans, Canadian-American inventor, scientist, and engineer who is credited with patenting the first practical telephone. He also co-founded the AT&T Corporation, American Telephone and Telegraph Company (AT&T) in 1885. Alexander Melville Bell, Bell's father, grandfather, and brother had all been associated with work on elocution and speech, and both his mother and wife were deaf, profoundly influencing Bell's life's work. His research on hearing and speech further led him to experiment with hearing devices, which eventually culminated in his being awarded the first United States patent law, U.S. patent for the telephone, on March 7, 1876. Bell considered his invention an intrusion on his real work as a scientist and refused to have a telephone in his study. Many other inventions marked Bell's later life, including ground-breaking work in Free-space optical commun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niche Market
A niche market is the subset of the market on which a product is appealed to a small group of consumers. The market niche defines the product features aimed at satisfying specific market needs, as well as the price range, production quality and the demographics that it is intended to target. It is also a small market segment. Sometimes, a product or service can be entirely designed to satisfy a niche market. Not every product can be defined by its market niche. The niche market is highly specialized, and aiming to survive among the competition from numerous super companies. Even established companies create products for different niches; Hewlett-Packard has all-in-one machines for printing, scanning and faxing targeted for the home office niche, while at the same time having separate machines with one of these functions for big businesses. In practice, product vendors and trade businesses are commonly referred to as ''mainstream providers'' or ''narrow demographics niche market pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Consolidated Telephone Co
Consolidated may refer to: Companies *Consolidated Aircraft, an American aircraft manufacturer active 1923–1943 *Consolidated Communications, an American broadband and business communications provider *Consolidated Edison, an American energy company that traces its lineage to 1823 *Consolidated Foods, an American food company later known as Sara Lee Corporation * Consolidated Papers, Inc., an American paper manufacturer active during the 20th century *Consolidated Railway (other), several American railroads *Consolidated Steel Corporation, an American steel and shipbuilding business formed in 1929 *Consolidated Stock Exchange of New York, active 1885–1926 Other uses *Consolidated (band), American radical activist music group formed in 1989 **''¡Consolidated!'', a 1989 EP by the group *Consolidated city-county, a form of local government in the United States *Consolidated financial statement * Consolidated rental car facility *Consolidated school or school district; se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
