when was air conditioning invented?
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The 19th century British scientist and inventor, Michael Faraday discovered that compressing and liquefying a certain gas could chill air when the liquified gas was allowed to evaporate. His idea remained largely theoretical.\n\nOne of the first uses of air conditioning for personal comfort was in 1902 when the New York Stock Exchange's new building was equipped with a central cooling as well as heating system. Alfred Wolff, an engineer from Hoboken, New Jersey who is considered the forerunner in the quest to cool a working environment, helped design the new system, transferring this budding technology from textile mills to commercial buildings.
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The first hand-powered cleaner using vacuum principles may have been the "Whirlwind", invented in Chicago in 1865.\n\nThe first powered cleaner employing a vacuum was patented by H. Cecil Booth, a British engineer, in 1901. He noticed a device used in trains that blew dust off the chairs, and thought it would be much more useful to have one that sucked dust. He tested the idea by laying a handkerchief on the seat of a dinner chair, putting his mouth to it and sucking hard. He nearly choked, but upon seeing the dust and dirt collected on the underside of the handkerchief he realised the idea could work. Booth worked to create a device operating on such principles, and patented such a machine in Britain: the large device, known as the Puffing Billy, was drawn by horses and parked outside the building to be cleaned; suction was then provided by an internal-combustion engine burning petrol (gasoline). However, Booth never achieved great success with his invention.
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ok remember that freon or r134 are used in AC but is not like it is a substance that stays cold... you to compress it in order to make it liquid and then it absorves heat and evaporates completing the cycle... if you are looking for a sort of system that will make something stay cool.. .hmmm man it is called Air Conditioned
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deliberate. AC uses same principle as the refridgerator, so after the fridges caught on, it was only a matter of time till somebody found a new use for technology.
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He invented the world's first alternating current (AC) radio tube which enabled radios to be powered by ordinary household current.
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"The first of the "modern" computers was invented during World War II, in 1941 by a German engineer named Konrad Zuse. The computer was called the Z3 and was used to help design German airplanes and missles."
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Here is a nice article on the topic, titled a History of Nebulization:\n\nhttp://www.liebertonline.com/doi/abs/10.1089/08942680152007918\n\nHope that helps!
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To get the most out of your room air conditioner, you'll need to consider the size of the unit that best suits your needs.\nThe cooling capacity of room air conditioners is measured in British thermal units per hour, or Btu/h. To figure out the maximum cooling capacity for a room, you will first need to calculate the size of the room where the air conditioner will be placed.\nTo do this, simply multiply the width of the room by the length of the room.  Use the following information and formulars to help you with calculating your air conditioning requirements:\n\n\nHeat Load\n\nThe amount of heat generated is known as the heat gain or heat load. Heat is measured in either British Thermal Units (BTU) or Kilowatts (KW). 1KW is equivalent to 3412BTUs.  The heat load depends on a number of factors, by taking into account those that apply in your circumstances and adding them together a reasonably accurate measure of the total heat can be calculated. Factors include: \n\nThe floor area of the room\n The size and position of windows, and whether they have blinds or shades \nThe number of room occupants (if any) \nThe heat generated by equipment \nThe heat generated by lighting \nArea of Room\n\nThe amount of cooling required depends on the area of the room. To calculate the area in square metres:\n\n\nRoom Area BTU = Length (m) x Width (m) x 337\n\n\nWindow Size and Position\n\nIf, your room has no windows, you can ignore this part of the calculation. If, however there are windows you need to take the size and orientation into account.\n\n\nSouth Window BTU = South Facing window Length (m) x Width (m) x 870\nNorth Window BTU = North Facing windows Length (m) x Width (m) x 165\nIf there are no blinds on the windows multiply the result(s) by 1.5.\nAdd together all the BTUs for the windows.\n\nWindows BTU = South Window(s) BTU + North Window(s) BTU\n\n\nOccupants\n\nYou will have to take that into account people who normally working in the space. The heat output is around 400 BTU per person.  \n\nTotal Occupant BTU = Number of occupants x 400\n\n\nEquipment\n\nClearly most heat in a room is generated by the equipment. This is trickier to calculate that you might think. The wattage on equipment is the maximum power consumption rating, the actual power consumed may be less. However it is probably safer to overestimate the wattage than underestimate it.\n\n\nEquipment BTU = Total wattage for all equipment x 3.5\n\n\nLighting\n\nTake the total wattage of the lighting and multiply by 4.25.\n\n\nLighting BTU = Total wattage for all lighting x 4.25\n\n\nTotal Cooling Required\n\nAdd all the BTUs together.\n\nTotal Heat Load = Room Area BTU + Windows BTU + Total Occupant BTU + Equipment BTU + Lighting BTU\n\nThis is the amount of cooling required so you need one or more air conditioning units to handle that amount of heat.\n\n--------------------\n\nGeneral thumb rule \n\n100 sqr ft area with roof height of 9 - 10 ft will need 1 Ton AC unit.
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An air conditioner inverter is part of a microprocessor-controlled system to provide more precise temperature control and less on-off compressor cycling. The inverter works in conjunction with a variable-speed motor which drives the compressor. These systems are said to be more efficient at part load than older systems. The references will give you the general idea.
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1) The Telephone \nThe telephone is an instrument that converts voice and sound signals into electrical impulses for transmission by wire to a different location, where another telephone receives the electrical impulses and turns them back into recognizable sounds. In 1875, Alexander Graham Bell built the first telephone that transmitted electrically the human voice.\n2) The History of Computers\nThere are many major milestones in the history of computers, starting with 1936, when Konrad Zuse built the first freely programmable computer.\n3) Television \nIn 1884, Paul Nipkow sent images over wires using a rotating metal disk technology with 18 lines of resolution. Television then evolved along two paths, mechanical based on Nipkow's rotating disks, and electronic based on the cathode ray tube. American Charles Jenkins and Scotsman John Baird followed the mechanical model while Philo Farnsworth, working independently in San Francisco, and Russian émigré Vladimir Zworkin, working for Westinghouse and later RCA, advanced the electronic model.\n4) The Automobile\nIn 1769, the very first self-propelled road vehicle was invented by French mechanic, Nicolas Joseph Cugnot. However, it was a steam-powered model. In 1885, Karl Benz designed and built the world's first practical automobile to be powered by an internal-combustion engine. In 1885, Gottlieb Daimler took the internal combustion engine a step further and patented what is generally recognized as the prototype of the modern gas engine and later built the world's first four-wheeled motor vehicle.\n5) The Cotton Gin \nEli Whitney patented the cotton gin on March 14, 1794. The cotton gin is a machine that separates seeds, hulls and other unwanted materials from cotton after it has been picked.\n6) The Camera\nIn 1814, Joseph Nicéphore Niépce created the first photographic image with a camera obscura, however, the image required eight hours of light exposure and later faded. Louis-Jacques-Mandé Daguerre is considered the inventor of the first practical process of photography in 1837.\n7) The Steam Engine\nThomas Savery was an English military engineer and inventor who in 1698, patented the first crude steam engine. Thomas Newcomen invented the atmospheric steam engine in 1712. James Watt improved Newcomen's design and invented what is considered the first modern steam engine in 1765.\n8) The Sewing Machine\nThe first functional sewing machine was invented by the French tailor, Barthelemy Thimonnier, in 1830. In 1834, Walter Hunt built America's first (somewhat) successful sewing machine. Elias Howe patented the first lockstitch sewing machine in 1846. Isaac Singer invented the up-and-down motion mechanism. In 1857, James Gibbs patented the first chain-stitch single-thread sewing machine. Helen Augusta Blanchard patented the first zig-zag stitch machine in 1873.\n9) The Light Bulb\nContrary to popular belief, Thomas Alva Edison didn't "invent" the light bulb, but rather he improved upon a 50-year-old idea. In 1809, Humphry Davy, an English chemist, invented the first electric light. In 1878, Sir Joseph Wilson Swan, an English physicist, was the first person to invent a practical and longer-lasting electic lightbulb (13.5 hours) with a carbon fiber filament. In 1879, Thomas Alva Edison invented a carbon filament that burned for forty hours.\n10) Penicillin \nPenicillin was discovered by Alexander Fleming in 1928. Andrew Moyer patented the first method of industrial production of penicillin in 1948.
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ventilation,ventilation,ventilation.
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Modern Refrigeration. \n\nSource(s):\n\nhttp://www.constructionbook.com/xq/asp/q...
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Refrigerators from the late 1800s until 1929 used the toxic gases, ammonia (NH3), methyl chloride (CH3Cl), and sulfur dioxide (SO2), as refrigerants. Several fatal accidents occurred in the 1920s because of methyl chloride leakage from refrigerators. People started leaving their refrigerators in their backyards. A collaborative effort began between three American corporations, Frigidaire, General Motors and DuPont to search for a less dangerous method of refrigeration.\n\nTo some extent, CFC's have been replaced by the less damaging hydro-chloro-fluoro-carbons (HCFCs), although concerns remain regarding HCFCs also. In some applications, hydro-fluoro-carbons (HFCs) have been used to replace CFCs. HFC's, which contain no chlorine or bromine, do not contribute at all to ozone depletion although they are potent greenhouse gases. The best known of these compounds is probably HFC-134a (R-134a), which in the United States has largely replaced CFC-12 (R-12) in automobile air conditioners.\n\nIn 1928, Thomas Midgley, Jr. aided by Charles Franklin Kettering invented a "miracle compound" called Freon. Freon represents several different chlorofluorocarbons, or CFCs, which are used in commerce and industry. The CFCs are a group of aliphatic organic compounds containing the elements carbon and fluorine, and, in many cases, other halogens (especially chlorine) and hydrogen. Freons are colorless, odorless, nonflammable, noncorrosive gases or liquids.\n\nBecause Freon is non-toxic, it eliminated the danger posed by refrigerator leaks. In just a few years, compressor refrigerators using Freon would become the standard for almost all home kitchens. In 1930, Thomas Midgley held a demonstration of the physical properties of Freon for the American Chemical Society by inhaling a lung-full of the new wonder gas and breathing it out onto a candle flame, which was extinguished, thus showing the gas's non-toxicity and non-flammable properties. Only decades later did people realize that such chlorofluorocarbons endangered the ozone layer of the entire planet.\n\nSide Note: CFCs, or Freon, are now infamous for greatly adding to the depletion of the earth's ozone shield. Leaded gasoline is also a major pollutant, and Thomas Midgley secretly suffered from lead poisoning because of his invention, a fact he kept hidden from the public.
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:) henry ford invent it in the 1900s
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It was invented by Micheal Faraday.  It was perfected by Robert Bunsen and his assistant, Peter Desaga.\n\nSee http://en.wikipedia.org/wiki/Bunsen_burner
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you probably need history of electricity. lte me give you a brief one.\nFrom the writings of Thales of Miletus it appears that Westerners knew as long ago as 600 B.C. that amber becomes charged by rubbing. There was little real progress until the English scientist William Gilbert in 1600 described the electrification of many substances and coined the term electricity from the Greek word for amber. As a result, Gilbert is called the father of modern electricity. In 1660 Otto von Guericke invented a crude machine for producing static electricity. It was a ball of sulfur, rotated by a crank with one hand and rubbed with the other. Successors, such as Francis Hauksbee, made improvements that provided experimenters with a ready source of static electricity. Today's highly developed descendant of these early machines is the Van de Graaf generator, which is sometimes used as a particle accelerator. Robert Boyle realized that attraction and repulsion were mutual and that electric force was transmitted through a vacuum (c.1675). Stephen Gray distinguished between conductors and nonconductors (1729). C. F. Du Fay recognized two kinds of electricity, which Benjamin Franklin and Ebenezer Kinnersley of Philadelphia later named positive and negative.\n\nThe Leyden Jar and the Quantitative Era\n\nProgress quickened after the Leyden jar was invented in 1745 by Pieter van Musschenbroek. The Leyden jar stored static electricity, which could be discharged all at once. In 1747 William Watson discharged a Leyden jar through a circuit, and comprehension of the current and circuit started a new field of experimentation. Henry Cavendish, by measuring the conductivity of materials (he compared the simultaneous shocks he received by discharging Leyden jars through the materials), and Charles A. Coulomb, by expressing mathematically the attraction of electrified bodies, began the quantitative study of electricity.\n\nA new interest in current began with the invention of the battery. Luigi Galvani had noticed (1786) that a discharge of static electricity made a frog's leg jerk. Consequent experimentation produced what was a simple electron cell using the fluids of the leg as an electrolyte and the muscle as a circuit and indicator. Galvani thought the leg supplied electricity, but Alessandro Volta thought otherwise, and he built the voltaic pile, an early type of battery, as proof. Continuous current from batteries smoothed the way for the discovery of G. S. Ohm's law (pub. 1827), relating current, voltage (electromotelinks" href="/encyclopedia/O/Ohmslaw.html">Ohm's law), and of J. P. Joule's law of electrical heating (pub. 1841). Ohm's law and the rules discovered later by G. R. Kirchhoff regarding the sum of the currents and the sum of the voltages in a circuit (see Kirchhoff's laws) are the basic means of making circuit calculations\nyou do need advanced studying in this but i think this will help u anywhere. best of luck!!
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The first patents on the use of SF6 as an interrupting medium was filed in Germany in 1938 by Vitaly Grosse (AEG) and independently later in the USA in July 1951 by H.J. Lingal, T.E. Browne and A.P. Storm (Westinghouse).