and "A microwave oven uses a magnetron microwave generator to produce microwaves at a frequency of approximately 2.4 GHz for the purpose of cooking food. Microwaves cook food by causing molecules of water and other compounds to vibrate. The vibration creates heat which warms the food. Since organic matter is made up primarily of water, food is easily cooked by this method." From http://www.gallawa.com/microtech/howcook.html: "Microwaves possess three basic characteristics: * Just as sunlight shines through a window, microwaves pass right through some materials.
Running head : Alexander Prokhorov Alexander Prokhorov Physics Mr.Horst Baelz Solatthika Roypromma 17/10/11 Alexander Prokhorov Alexander Prokhorov and his discoveries have greatly impacted our lives. He discovered masers and lasers. What are maser and a laser? Maser is stands for microwave amplification by stimulated emission of radiation. Laser stands for light amplification by stimulated emission of radiation.
Michelson was born in Prussia in 1872 and later moved to the United States where he joined the U.S. Navy. As an instructor in the Navy academy he was asked to demonstrate the Foucault method of measuring the speed of light and made several improvements on it. Michelson received a grant and built his first interferometer much like the one presently used. It consisted of an Argand lamp, two mirrors, two beam splitters and an eyepiece. The device was extremely sensitive to vibrations and wasn’t accurate until it was brought to the Potsdam Astrophysical Observatory in Berlin where it was mounted on a platform designed for an equatorial telescope.
This meaning electric / magnetic / spectrum. Radio waves are used to transmit radio and television signals. Radio waves can send sounds at the speed of light. The range of radio waves can be less than a centimeter to tens or even hundredths of meters. Radio waves are produced by coherent motion of electrons such as the antenna of a radio transmitter.
L A S E R S Did you know that some laser beams are small enough and powerful enough to drill two hundred holes on a spot as tiny as the head of a pin? The first major advancement in laser development came in 1954. This was the year that Charles H. Townes, an American physicist, created a device that amplified microwaves. This device was actually called a maser at first, which was short for Microwave Amplification by Stimulated Emission of Radiation Masers. It produced microwaves of just one frequency.
The Beginning The Radio was introduced to society because of the telegraph and the telephone. These inventions don’t do the same things but their similar branch of technology. “Radio technology began as “wireless telegraphy”. “It all started with the discovery of radio waves, electromagnetic waves that have the capacity to transmit music, speech, pictures and other data invisibly through air.” [Bellis] Majority of technology uses electromagnetic waves to send data information or TV broadcasts. During the 1860’s, Scottish physicist, James Clerk Maxwell predicted the existence of radio waves; and in 1886, German physicist, Heinrich Rudolph Hertz showed how fast the variation of electric current could be placed into space in the form of radio waves similar to light and heat.
Since fiber is much better than copper, its beginning to have many applications. Telephone and cable television companies are both begging to use fiber. Lines connecting central offices in companies are often using fiber. Power companies use it for communication because of its lack of electrical interference. Computing is one of the other main uses.
Optical amplifications were not taken seriously, until for very long, it had been postulated in 1916 by Elbert Einstein. The ones that proposes the building of an optical amplifier is Valentin A.Fabricant, which is a Russian engineer in his unpublished 1939 dissertation. However, serious attention and interest came only after Charles Townes used stimulated emissions to produce microwave oscillations in the Maser in1954. The first laser was built in 1960 by Theodore Main. Early laser developer proposed and saw amplification as a step to build a laser.
Conclusion References [1] Einstein, A. “On the quantum theory of radiation.” Phys. Z 18 (1917) 121-128. [2] Maiman, T. H. “Stimulated optical radiation in ruby.” Nature 187 (1960) 493-494. [3] G. Chapline and L. Wood.
This characteristic of microwaves, the efficiency with which they are concentrated in a narrow beam, is one reason why they can be used in cooking. You can produce a high-powered microwave beam in a small oven, but you can't do the same with radio waves, which are simply too long. Microwaves and their Use The idea of cooking with radiation may seem like a fairly new one, but in fact it reaches back thousands of years. Ever since mastering fire, man has cooked with infrared radiation, a close kin of the microwave. Infrared rays are what give you that warm glow when you put your hand near a room radiator or a hotplate or a campfire.