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86 Cards in this Set
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in (year), ---'s ----- experiment provided the first experimental evidence for ---theory |
1803; Thomas Young's double-slit interference experiment; a wave theory of light |
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by (years), --- had provided a convincing wave description of light and of other forms of electromagnetic radiation |
1860s and 1870s; James Clark Maxwell |
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--- is an electrical and magnetic disturbance that moves through space at the speed of light (c=----); according to |
electromagnetic wave; (c= 3.0 x 10(8) m/s); James Clark Maxwell |
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the combined field of electric and magnetic nature, which is produced by the oscillating charge on the antenna |
electromagnetic wave |
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combination of electric and magnetic fields |
electromagnetic (EM) wave |
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electromagnetic wave is also known as |
electromagnetic radiation |
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EM waves are arranged in an --- based on their (3) |
electromagnetic spectrum; frequency, wavelength, photon energy |
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EM waves have frequencies measured in cycles per second or --- |
hertz (Hz) |
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range of frequencies is referred to as the --- |
electromagnetic spectrum |
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in the electromagnetic spectrum, --- has the longest wavelengths |
radio waves |
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in the electromagnetic spectrum, --- has the highest frequencies |
gamma rays |
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each types of EM wave occupies a particular range of wavelength known as --- |
band |
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(7) EM waves arranged in increasing frequency |
radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays |
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infrared waves are produced by --- |
molecular vibrations |
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radio waves are produced by --- |
charges vibrating back and forth in antennas |
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infrared waves are sometimes called --- or --- |
heat or thermal radiation |
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light waves are caused by ---- |
the motion of electrons in atoms as they jump between different orbits |
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ultraviolet radiation and X-rays are produced by --- |
the motion of electrons in atoms |
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gamma rays ar produced by ---- |
the motion of charged particles in nuclei |
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one of the fundamentals of the universe and visible light is incredibly important to humans and a vast array of natural organisms |
electromagnetic spectrum |
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radiation energy that travels and spreads out as it goes |
EM spectrum |
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can be described in terms of a stream of particles, each traveling in a wave-like pattern and moving at the speed of light |
EM radiation |
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each particle in EM radiation contains a bundle of energy called --- |
photon |
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they are used to transmit radio and television signals |
radio waves |
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(2) radio wave bands |
AM (amplitude modulation) and FM (frequency modulation) bands |
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radio waves of the standard ---- have longer wavelength compared to the short radio waves for --- |
AM broadcast band; FM band |
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readily bends around buildings and other objects that might be present in their path |
wavelength of AM radio waves |
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-- reception is often poor in localities where -- radio waves come in loud and clear |
FM; AM |
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is a rate of oscillation in the range of about 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating curents that carry radio signals |
Radio frequency (RF) |
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the transmission and reception of radio waves are dependent on --- |
oscillating charges |
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radio development began as ---, a historical term for early radio telegraph communications techniques and practices, particularly those that were used during the first -- decades of radio (year to year) |
wireless telegraphy; three decades; (1887 to 1920) |
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the history of telecommunications can be rooted to the use of --- in (3) |
smoke signals in Africa, America, and some parts of Asia |
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As early as 1790s, the first ---- (---) was developed in ---, but it was not until 1830s that ---- has started to appear |
fixed semaphore system (visual telegraphy); Europe; electrical communication system |
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one of the early experiments in electrical telegraphy was an --- created by --- in 1809 |
electrochemical telegraph; Samuel Thomas von Sommering |
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--- and --- constructed the first commercial electrical telegraph in ---, while --- was also doing his own version of the same technology on the other side of Atlantic Ocean |
Sir Charles Wheatstone and Sir William Fothergill Cook; England; Samuel Morse |
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it was --- who showed mathematically that electromagnetic waves could propagate through free space |
James Clerk Maxwell |
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--- and many others demonstrated, on a laboratory scale, --- |
Heinrich Rudolf Hertz; radio wave propagation |
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--- experimented on the transmission and radiation of radio frequency energy and proposed for the telecommunication of information |
Nikola Tesla |
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in 1876, the --- was invented by --- |
conventional telephone; Alexander Graham Bell |
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in terms of radio communication, --- demonstrated --- within a two-mile distance using -- as a transmission medium in 1854 |
James Lindsay; wireless telegraphy; water |
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(2) developed the Slaby-Arco Wireless System |
Adolf Slaby and Georg vin Arco |
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Adolf Slaby and Georg von Arco developed the --- |
Slaby-Arco Wireless system |
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in 1900, --- made a weak transmission of voice over the airwaves |
Reginald Fessenden |
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he was the first to demonstrate the application of radio in commercial, military, and marine communications and started a company for the development and propagation of radio communication services and equipment |
Guglielmo Marconi |
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in (month and yr), scottish inventor --- was able to obtain moving pictures with halftone shades, which were, by most accounts, the first true television pictures |
October 1925; John Logie Baird |
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John Logie Baird's device was known as ---, which was the basis of semi-experimental broadcasts done by the --- beginning (date) |
mechanical television; British Broadcasting Corporation; September 30, 1929 |
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are extremely high-frequency radio waves that are made by various types of transmitters |
microwaves |
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an electronic device, which with the aid of an antenna, produces radio waves |
transmitter |
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he discovered in (year) the existence of infrared by passing sunlight through a --- |
Sir William Herschel; 1800; prism |
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prism divides into a rainbow of colors called a ---, which contains all the colors that make up sunlight |
spectrum |
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type/form of light which we cannot see with out eyes |
infrared |
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the the EM radiation with a wavelength longer than that of visible light, and includes most of the thermal radiation emitted by objects near room temperature |
infrared |
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infrared light that is closest in wavelength to the visible light and are not hot at all |
near infrared light |
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infrared light that is closer to the microwave region of the EM spectrum, and are thermal, which means they can be experienced in the form of heat such as sunlight, fire, or radiator |
far infrared light |
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can be used to remotely determine the temperature of objects (if emissivity is known) |
infrared radiation |
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infrared radiation is known as --- or --- as in the case of very hot objects |
thermography or pyrometry |
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the portion of EM radiation that is visible to the human eye |
visible light |
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whats colors have the longest and shortest wavelength |
red and violet |
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an EM radiation with a wavelength shorter than that of visible light, but longer than X-rays |
ultraviolet |
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most of the ultraviolet radiation in sunlight is absorbed by --- in Earth's atmosphere, which forms the --- of the lower stratosphere |
oxygen; ozone layer |
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refers to any type of electromagnetic radiation that does not carry enough energy per quantum to ionize atoms or molecules, that is, to completely remove an electron from an atom or molecule |
non-ionizing radiation |
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are high-energy waves which have great pentrating power and are used extensively in medical applications and in inspecting welds |
x-rays |
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x-radiation is called ---, after ---, who is generally credited as its discoverer |
Röntgen radiation; Wilhelm Conrad Röntgen |
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very high frequency x-rays |
hard rays |
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are generated by radioactive atoms and in nuclear explosions, and are used in many medical applications |
gamma rays |
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in the procedure called ---, multiple concentrated beams of gamma rays are directed on the growth in order to kill the cancerous cells |
gamma-knife surgery |
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--- thought that light consisted of streamers emitted by the eye, and gained support from --- |
Plato; Euclid |
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believed that light originated from luminous bodies in the form of very fine particles |
Pythagoras |
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a forerunner of Plato, believed that light is composed of high-speed waves of some sort |
Empedocles |
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(2) theories on the basic nature of light |
Wave (Undulatory) Theory, and Quantum Theory of Light |
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explains that light has a wave motion that starts from a vibrating body and is transmitted at high speed |
Wave (Undulatory) Theory |
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on of the proponents of the wave theory was ---, who explained the refelction of light using wave motion |
Christian Huygens |
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according to the ---, different points of a wave front of light set up a series of secondary waves. Since light can pass through a vacuum, he explained that light may travel through a medium known as ---, a mysterious substance which is not air |
Huygen's Principle; "ether" |
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in 1704, --- contradicted the Wave Theory as he described light as a stream of particles or corpuscles. Based on his theory known as the ---, light consists of tiny particles of matter emitted by a source that travel only in straight lines called -- |
Sir Isaac Newton; Corpuscular or Emission Theory; rays |
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---, in his experiment in 1801, was able to study the interference and diffraction of light |
Thomas Young |
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Thomas Young was able to study the (2) |
interference and diffraction of light |
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--- constructed an oscillating electrical circuit, which showed that changing electric and magnetic fields could produce electromagnetic radiation that could travel through a vacuum |
James Clerk Maxwell |
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light was eventually proved to be --- as Heinrich Hertz demonstrated the existence of electromagnetic waves that exhibit the same properties as the light |
electromagnetic |
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he hypothesized that the vibrating electrons in incandescent lights could only have energies restricted to certain values. He introduced the phenomenon known as ---, which according to him was emitted in discrete bundles of energy called --- |
Max Planck; blackbody radiation; quanta (quantum for plural) |
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states that light is composed of bundles of wave enery called ---; by |
Quantum Theory of Light; photons; by Albert Einstein |
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if light falls on a clean surface of metals such as potassium or sodium, electrons are emitted by the surface. this is called the --- |
photoelectric effect |
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in 1923, ---'s study of the scattering of x-rays by electrons all required the assumption of a particular nature for electromagnetic radiation without in any way invalidating the wave theory of light |
Arthur Compton |
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he proposed that every particle of matter is somehow endowed with a wave to guide it as it travels. hence, the ---- was credited |
Louis Victor de Brogile; particle-wave duality of wave |
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was the first to hypothesize that light has a finite speed |
Galileo |
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in 1675, ---, a Danish astronomer, became the first person to measure the speed of light over an astronomical distance |
Ole Reomer |
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the current accepted value for the speed of light in empty space was determined through the experiments conducted by physicist --- |
Albert A. Michaelson |
