What Is Electromagnetic Radiation?

Total Page：16

File Type：pdf, Size：1020Kb

What Is Electromagnetic Radiation? How are radio waves, visible light, and X-rays similar? They are all types of electromagnetic radiation. All three travel — radiate — and are made or detected by electronic (or magnetic) sensors, like a T.V., a digital camera, or a dentist’s X-ray machine. Types of electromagnetic radiation with which we are most familiar include ultraviolet light (causing sunburn), infrared light (in remote controls), and microwaves (in ovens). Electromagnetic radiation is made of electromagnetic waves. It is classified by the distance from the crest of one wave to the crest of the next — the wavelength. These waves can be thousands of miles long, like radiowaves, or smaller than an atom, like gamma rays! Collectively, these wavelengths make a spectrum — the electromagnetic spectrum. The shorter the wavelength, the more energetic the electromagnetic radiation. Radio waves, including microwaves, have long wavelengths and relatively low energy levels. Visible light, ultraviolet rays, X-rays, and gamma rays have shorter wavelengths and correspondingly higher levels of energy. The wavelengths of ultraviolet light, X-rays, and gamma rays are short enough to interact with human tissue and even alter DNA. What Is Reflectance Spectroscopy? Spectroscopy is the study of the electromagnetic radiation emitted, absorbed, or reflected by an object. Reflectance spectroscopy is the study of electromagnetic radiation that is reflected from an object, such as a leaf, a rock, or ice on a distant planet’s surface. We have a source of electromagnetic radiation right in our solar system — our Sun! The light we see with our eyes coming from moons and planets is actually reflected sunlight. Scientists can study this visible light, and other portions of the electromagnetic spectrum reflecting from planets and moons, to learn about their physical and chemical properties. .

Copy Link

Recommended publications

1 LIGHT PHYSICS Light and Lighting Francesco Anselmo Light Intro Light Animates and Reveals Architecture
1 LIGHT PHYSICS Light and Lighting Francesco Anselmo Light intro Light animates and reveals architecture. Architecture cannot fully exist without light, since without light there would be nothing to see. Yet in architectural design light is usually either expected from nature or developed as an add-on attachment very late in the design process. The course explores the symbiotic relationship between architecture and light. As much as light can reveal architecture, architecture can animate light, making it bounce, scatter, refract, altering its spectrum and colour perception, absorbing it or reﬂecting it, modulating its path and strength in both space and time. It aims at developing a sensibility and intuition to the qualities of light, whilst giving the physical and computational tools to explore and validate design ideas. 4 7 1 2 5 3 6 1 LIGHT PHYSICS 4 LIGHT ELECTRIC 7 LIGHT CONNECTED 2 LIGHT BIOLOGY 5 LIGHT ARCHITECTURE 3 LIGHT NATURAL 6 LIGHT VIRTUAL Reading list Books Free online resources Bachelard, Gaston. The poetics of space, Beacon Press 1992 • http://hyperphysics.phy-astr.gsu.edu/hbase/ligcon.html Banham, Reyner. The architecture of the well-tempered Environment, Chicago University Press 1984 • http://thedaylightsite.com/ Bazerman, Charles. The languages of Edison’s light, MIT Press 2002 Berger, John. Ways of seeing, Pearson Education, Limited, 2002 • http://issuu.com/lightonline/docs/handbook-of-lighting-design Berger, John. About looking, Bloomsbury Publishing 2009 • http://www.radiance-online.org/ Bluhm, Andreas. Light! The industrial age 1750-1900, Carnegie Museum of Art 2000 Boyce, Peter R. Human Factors in Lighting, Taylor & Francis 2003 Calvino, Italo.
[Show full text]
Download the DIA Color Chart
DEMI-PERMANENT HAIRCOLOR 2 COMPLIMENTARY LINES OF HAIRCOLOR Each with its own benefit & expertise both provide maximum creativity & freedom ADVANCED ALKALINE TECHNOLOGY GENTLE ACID TECHNOLOGY HIGH PERFORMANCE HIGH PERFORMANCE • Demi-permanent crème • Luminous demi-permanent gel-crème • Rich tones, exceptional softness • Zero lift • Covers up to 70% grey • Intense care for the hair THE PROCESS THE PROCESS • Lifts (up to 1.5 Levels with 15-vol), then deposits • Zero lift, deposit only BEFORE COLOR DURING COLOR AFTER COLOR BEFORE COLOR DURING COLOR AFTER COLOR On natural hair, the cuticle The alkaline agents slightly open DIA Richesse has the ability to lighten up On color-treated & DIA Light has an acid The cationic polymers in scales are closed. the hair fiber allowing colorants to 1.5 levels, cover up to 70% white hair sensitized hair, the cuticle pH close to the natural pH of the hair. DIA Light have a resurfacing to penetrate the cuticle. & create rich, profound tones. scales are already open. effect on the cuticle, leaving There is no lift with gentle penetration the hair with amazing shine. of colorants for long lasting color. ADVANCED ALKALINE TECHNOLOGY ADVANCED ALKALINE TECHNOLOGY HIGH PERFORMANCE • Demi-permanent crème • Rich tones, exceptional softness • Covers up to 70% grey THE PROCESS • Lifts (up to 1.5 Levels with 15-vol), then deposits BEFORE COLOR DURING COLOR AFTER COLOR On natural hair, the cuticle The alkaline agents slightly open DIA Richesse has the ability to lighten scales are closed. the hair fiber allowing colorants up to 1.5 levels, cover up to 70% white to penetrate the cuticle.
[Show full text]
WHITE LIGHT and COLORED LIGHT Grades K–5
WHITE LIGHT AND COLORED LIGHT grades K–5 Objective This activity offers two simple ways to demonstrate that white light is made of different colors of light mixed together. The first uses special glasses to reveal the colors that make up white light. The second involves spinning a colorful top to blend different colors into white. Together, these activities can be thought of as taking white light apart and putting it back together again. Introduction The Sun, the stars, and a light bulb are all sources of “white” light. But what is white light? What we see as white light is actually a combination of all visible colors of light mixed together. Astronomers spread starlight into a rainbow or spectrum to study the specific colors of light it contains. The colors hidden in white starlight can reveal what the star is made of and how hot it is. The tool astronomers use to spread light into a spectrum is called a spectroscope. But many things, such as glass prisms and water droplets, can also separate white light into a rainbow of colors. After it rains, there are often lots of water droplets in the air. White sunlight passing through these droplets is spread apart into its component colors, creating a rainbow. In this activity, you will view the rainbow of colors contained in white light by using a pair of “Rainbow Glasses” that separate white light into a spectrum. ! SAFETY NOTE These glasses do NOT protect your eyes from the Sun. NEVER LOOK AT THE SUN! Background Reading for Educators Light: Its Secrets Revealed, available at http://www.amnh.org/education/resources/rfl/pdf/du_x01_light.pdf Developed with the generous support of The Charles Hayden Foundation WHITE LIGHT AND COLORED LIGHT Materials Rainbow Glasses Possible white light sources: (paper glasses containing a Incandescent light bulb diffraction grating).
[Show full text]
Absorption of Light Energy Light, Energy, and Electron Structure SCIENTIFIC
Absorption of Light Energy Light, Energy, and Electron Structure SCIENTIFIC Introduction Why does the color of a copper chloride solution appear blue? As the white light hits the paint, which colors does the solution absorb and which colors does it transmit? In this activity students will observe the basic principles of absorption spectroscopy based on absorbance and transmittance of visible light. Concepts • Spectroscopy • Visible light spectrum • Absorbance and transmittance • Quantized electron energy levels Background The visible light spectrum (380−750 nm) is the light we are able to see. This spectrum is often referred to as “ROY G BIV” as a mnemonic device for the order of colors it produces. Violet has the shortest wavelength (about 400 nm) and red has the longest wavelength (about 650–700 nm). Many common chemical solutions can be used as filters to demonstrate the principles of absorption and transmittance of visible light in the electromagnetic spectrum. For example, copper(II) chloride (blue), ammonium dichromate (orange), iron(III) chloride (yellow), and potassium permanganate (red) are all different colors because they absorb different wave- lengths of visible light. In this demonstration, students will observe the principles of absorption spectroscopy using a variety of different colored solutions. Food coloring will be substituted for the orange and yellow chemical solutions mentioned above. Rare earth metal solutions, erbium and praseodymium chloride, will be used to illustrate line absorption spectra. Materials Copper(II) chloride solution, 1 M, 85 mL Diffraction grating, holographic, 14 cm × 14 cm Erbium chloride solution, 0.1 M, 50 mL Microchemistry solution bottle, 50 mL, 6 Potassium permanganate solution (KMnO4), 0.001 M, 275 mL Overhead projector and screen Praseodymium chloride solution, 0.1 M, 50 mL Red food dye Water, deionized Stir rod, glass Beaker, 250-mL Tape Black construction paper, 12 × 18, 2 sheets Yellow food dye Colored pencils Safety Precautions Copper(II) chloride solution is toxic by ingestion and inhalation.
[Show full text]
Light, Color, and Atmospheric Optics
Light, Color, and Atmospheric Optics GEOL 1350: Introduction To Meteorology 1 2 • During the scattering process, no energy is gained or lost, and therefore, no temperature changes occur. • Scattering depends on the size of objects, in particular on the ratio of object’s diameter vs wavelength: 1. Rayleigh scattering (D/ < 0.03) 2. Mie scattering (0.03 ≤ D/ < 32) 3. Geometric scattering (D/ ≥ 32) 3 4 • Gas scattering: redirection of radiation by a gas molecule without a net transfer of energy of the molecules • Rayleigh scattering: absorption extinction 4 coefficient s depends on 1/ . • Molecules scatter short (blue) wavelengths preferentially over long (red) wavelengths. • The longer pathway of light through the atmosphere the more shorter wavelengths are scattered. 5 • As sunlight enters the atmosphere, the shorter visible wavelengths of violet, blue and green are scattered more by atmospheric gases than are the longer wavelengths of yellow, orange, and especially red. • The scattered waves of violet, blue, and green strike the eye from all directions. • Because our eyes are more sensitive to blue light, these waves, viewed together, produce the sensation of blue coming from all around us. 6 • Rayleigh Scattering • The selective scattering of blue light by air molecules and very small particles can make distant mountains appear blue. The blue ridge mountains in Virginia. 7 • When small particles, such as fine dust and salt, become suspended in the atmosphere, the color of the sky begins to change from blue to milky white. • These particles are large enough to scatter all wavelengths of visible light fairly evenly in all directions.
[Show full text]
How Do Radioactive Materials Move Through the Environment to People?
5. How Do Radioactive Materials Move Through the Environment to People? aturally occurring radioactive materials Radionuclides can be removed from the air in Nare present in our environment and in several ways. Particles settle out of the our bodies. We are, therefore, continuously atmosphere if air currents cannot keep them exposed to radiation from radioactive atoms suspended. Rain or snow can also remove (radionuclides). Radionuclides released to them. the environment as a result of human When these particles are removed from the activities add to that exposure. atmosphere, they may land in water, on soil, or Radiation is energy emitted when a on the surfaces of living and non-living things. radionuclide decays. It can affect living tissue The particles may return to the atmosphere by only when the energy is absorbed in that resuspension, which occurs when wind or tissue. Radionuclides can be hazardous to some other natural or human activity living tissue when they are inside an organism generates clouds of dust containing radionu- where radiation released can be immediately clides. absorbed. They may also be hazardous when they are outside of the organism but close ➤ Water enough for some radiation to be absorbed by Radionuclides can come into contact with the tissue. water in several ways. They may be deposited Radionuclides move through the environ- from the air (as described above). They may ment and into the body through many also be released to the water from the ground different pathways. Understanding these through erosion, seepage, or human activities pathways makes it possible to take actions to such as mining or release of radioactive block or avoid exposure to radiation.
[Show full text]
The Electromagnetic Spectrum
The Electromagnetic Spectrum Wavelength/frequency/energy MAP TAP 2003-2004 The Electromagnetic Spectrum 1 Teacher Page • Content: Physical Science—The Electromagnetic Spectrum • Grade Level: High School • Creator: Dorothy Walk • Curriculum Objectives: SC 1; Intro Phys/Chem IV.A (waves) MAP TAP 2003-2004 The Electromagnetic Spectrum 2 MAP TAP 2003-2004 The Electromagnetic Spectrum 3 What is it? • The electromagnetic spectrum is the complete spectrum or continuum of light including radio waves, infrared, visible light, ultraviolet light, X- rays and gamma rays • An electromagnetic wave consists of electric and magnetic fields which vibrates thus making waves. MAP TAP 2003-2004 The Electromagnetic Spectrum 4 Waves • Properties of waves include speed, frequency and wavelength • Speed (s), frequency (f) and wavelength (l) are related in the formula l x f = s • All light travels at a speed of 3 s 108 m/s in a vacuum MAP TAP 2003-2004 The Electromagnetic Spectrum 5 Wavelength, Frequency and Energy • Since all light travels at the same speed, wavelength and frequency have an indirect relationship. • Light with a short wavelength will have a high frequency and light with a long wavelength will have a low frequency. • Light with short wavelengths has high energy and long wavelength has low energy MAP TAP 2003-2004 The Electromagnetic Spectrum 6 MAP TAP 2003-2004 The Electromagnetic Spectrum 7 Radio waves • Low energy waves with long wavelengths • Includes FM, AM, radar and TV waves • Wavelengths of 10-1m and longer • Low frequency • Used in many
[Show full text]
Physics, Chapter 40: Light As a Wave Motion
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Robert Katz Publications Research Papers in Physics and Astronomy 1-1958 Physics, Chapter 40: Light as a Wave Motion Henry Semat City College of New York Robert Katz University of Nebraska-Lincoln, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/physicskatz Part of the Physics Commons Semat, Henry and Katz, Robert, "Physics, Chapter 40: Light as a Wave Motion" (1958). Robert Katz Publications. 177. https://digitalcommons.unl.edu/physicskatz/177 This Article is brought to you for free and open access by the Research Papers in Physics and Astronomy at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Robert Katz Publications by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. 40 Light as a Wave Motion 40-1 Wave Versus Particle Let us recount some of the characteristics of the motion of particles and the propagation of waves, with a view toward analyzing the behavior of light. In accordance with Newton's first law, a particle moves in a straight-line path in the absence of external forces. Thus we might infer, as Newton suggested, that light is composed of particles, and that, in a continuous medium, there is no deflecting force on the light particles. At the interface between two media, light may be propagated in a straight line parallel to the interface. Thus even at an interface there is no force on the particles of light unless the light passes through the interface, and in that event the force acting must be perpendicular to the interface.
[Show full text]
Radionuclides (Including Radon, Radium and Uranium)
Radionuclides (including Radon, Radium and Uranium) Hazard Summary Uranium, radium, and radon are naturally occurring radionuclides found in the environment. No information is available on the acute (short-term) noncancer effects of the radionuclides in humans. Animal studies have reported inflammatory reactions in the nasal passages and kidney damage from acute inhalation exposure to uranium. Chronic (long-term) inhalation exposure to uranium and radon in humans has been linked to respiratory effects, such as chronic lung disease, while radium exposure has resulted in acute leukopenia, anemia, necrosis of the jaw, and other effects. Cancer is the major effect of concern from the radionuclides. Radium, via oral exposure, is known to cause bone, head, and nasal passage tumors in humans, and radon, via inhalation exposure, causes lung cancer in humans. Uranium may cause lung cancer and tumors of the lymphatic and hematopoietic tissues. EPA has not classified uranium, radon or radium for carcinogenicity. Please Note: The main sources of information for this fact sheet are EPA's Integrated Risk Information System (IRIS) (5), which contains information on oral chronic toxicity and the RfD for uranium, and the Agency for Toxic Substances and Disease Registry's (ATSDR's) Toxicological Profiles for Uranium, Radium, and Radon. (1) Uses Uranium is used in nuclear power plants and nuclear weapons. Very small amounts are used in photography for toning, in the leather and wood industries for stains and dyes, and in the silk and wood industries. (2) Radium is used as a radiation source for treating neoplastic diseases, as a radon source, in radiography of metals, and as a neutron source for research.
[Show full text]
6.2.43A Radiation-Dominated Model of the Universe
6 BIG BANG COSMOLOGY – THE EVOLVING UNIVERSE 6.2.43A radiation-dominated model of the Universe R We have just seen that in the early Universe, the dominant energy density is that due to the radiation within the Universe. The Friedmann equation that was described in Chapter 5 (Box 5.4) can be solved for such conditions and the way in which the scale factor varies with time for such a model is shown in Figure 6.7. One important feature of such a model is that the scale factor varies in the following way: R(t) ∝ t1/2 (6.17) 0 t −4 Because the energy density of radiation is dominant for times when R(t)/R(t0) < 10 , all cosmological models which start at t = 0 with R(0) = 0, will go through a phase Figure 6.73The evolution of the that is well described by this radiation-dominated model. Thus we are in the rather scale factor with time in a remarkable position that regardless of which type of cosmological model best cosmological model in which the dominant contribution to the describes the Universe at the present, we can be reasonably confident that we energy density arises from the know how the scale factor varied with time in the first few tens of thousands of radiation within the Universe years of the big bang. (i.e. during the radiation-dominated However, the temperature of the background radiation varies with scale factor era). according to T(t) ∝ 1/R(t) (Equation 6.6). It follows that during the radiation- dominated era the temperature of the background radiation varies with time according to T(t) ∝ t −1/2 (6.18) This describes how temperature changes with time in an expanding universe where the energy density of radiation is the dominant component.
[Show full text]
Liquicolor Permanente Shades 07-10-12.Pdf
LIQUICOLOR PERMANENTE INTENSE INTENSE INTENSE INTENSE GOLD RED NEUTRAL (RN) INTENSE RED (RR) RED VIOLET (RV) RED VIOLET (RRV) BASE INTENSE NEUTRAL (NN) NEUTRAL (N) ASH (A) ASH (A) ASH (AA) ASH (AA) NEUTRAL(GN) GOLD (G) REDPELIRROJO NEUTRAL (RN) RED (R) INTENSEPELIRROJO RED (RR) REDPELIRROJO VIOLET (RV) REDPELIRROJO VIOLET (RRV) NEUTRAL INTENSO NEUTRAL CENIZO CENIZO CENIZO INTENSO CENIZO INTENSO DORADO NEUTRAL GOLDDORADO (G) PELIRROJONEUTRAL PELIRROJORED (R) PELIRROJOINTENSO PELIRROJOVIOLETA VIOLETAPELIRROJO INTENSO LEVEL/NIVEL DORADO NEUTRAL PELIRROJO INTENSO VIOLETA VIOLETA INTENSO 12 HIGH-LIFT BLONDE 12N/HL-N 12A/HL-V 12AA-B/HL-B 12AA-BV 12G / HL-G HIGH LIFT HIGH LIFT HIGH LIFT ULTRA HIGH LIFT ULTRA HIGH LIFT GOLDEN BLONDE NEUTRAL BLONDE COOL BLONDE COOL BLONDE BLUE COOL BLONDE BLUE VIOLET 10 LIGHTEST BLONDE RUBIO CLARÍSIMO 10N/12B1 10GN/12G2 OUR FIRST NN 10G / 12G LIGHTEST NEUTRAL BLONDE LIGHTEST GOLD LIQUID COLOR LIGHTEST GOLDEN BLONDE blondest beige NEUTRAL BLONDE blondest blonde blondest gold 9 VERY LIGHT BLONDE RUBIO MUY CLARO 9NN 9N/89N 9A/26D 9A-N/40D 9AA/20D 9AA-BV/30D VERY LIGHT RICH VERY LIGHT VERY LIGHT VERY LIGHT COOL VERY LIGHT ULTRA VERY LIGHT ULTRA COOL NEUTRAL BLONDE NEUTRAL BLONDE COOL BLONDE NEUTRAL BLONDE COOL BLONDE BLONDE BLUE VIOLET lightest neutral blonde winter wheat topaz arctic blonde flaxen blonde 8 LIGHT BLONDE RUBIO CLARO 8NN 8N/88N 8A / 28D 8GN/27G 8RN / 71RG 8R / 29R LIGHT RICH LIGHT LIGHT COOL BLONDE LIGHT GOLD NEUTRAL LIGHT RED NEUTRAL LIGHT RED BLONDE NEUTRAL BLONDE NEUTRAL BLONDE autumn mist BLONDE
[Show full text]
Electromagnetic Spectrum
Electromagnetic Spectrum Why do some things have colors? What makes color? Why do fast food restaurants use red lights to keep food warm? Why don’t they use green or blue light? Why do X-rays pass through the body and let us see through the body? What has the radio to do with radiation? What are the night vision devices that the army uses in night time fighting? To find the answers to these questions we have to examine the electromagnetic spectrum. FASTER THAN A SPEEDING BULLET MORE POWERFUL THAN A LOCOMOTIVE These words were used to introduce a fictional superhero named Superman. These same words can be used to help describe Electromagnetic Radiation. Electromagnetic Radiation is like a two member team racing together at incredible speeds across the vast regions of space or flying from the clutches of a tiny atom. They travel together in packages called photons. Moving along as a wave with frequency and wavelength they travel at the velocity of 186,000 miles per second (300,000,000 meters per second) in a vacuum. The photons are so tiny they cannot be seen even with powerful microscopes. If the photon encounters any charged particles along its journey it pushes and pulls them at the same frequency that the wave had when it started. The waves can circle the earth more than seven times in one second! If the waves are arranged in order of their wavelength and frequency the waves form the Electromagnetic Spectrum. They are described as electromagnetic because they are both electric and magnetic in nature.
[Show full text]