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Power Waves. 60 Hz. 5X10^6 m. Result from alternating currents in electric power lines Little practical use Hum produced by induction Possible side effects- harmful biological effects on cells and tissues . Inconclusive evidence of a link between cancer and living near power lines
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Power Waves 60 Hz 5X10^6 m
Result from alternating currents in electric power lines • Little practical use • Hum produced by induction • Possible side effects- harmful biological effects on cells and tissues
Inconclusive evidence of a link between cancer and living near power lines • A study in 1979 showed a possible association • childhood leukemia • inadequate evidence that these magnetic fields cause other cancers in children
Radio & TV WavelengthsBy: David Runowski, Alex Patin, and Evan Oszaroff TV and Radio wavelengths are transverse. Wavelengths range from thousands of meters to about one meter. Their frequency ranges usually from 500kHz-1000MHz For AM-530- 1710kHz For FM- 88-108Mhz TV- 30MHz-300MHz
Natural sources come from lightning . Unnatural sources come from satellites. Astronomical objects are a source from space. Detection/ How they work Antenna are the main method in receiving TV and Radio waves. A common radio antenna is a simple conductor and is able to manipulate electrical charges created by the electrical and magnetic field generated from the transmitter source. Sources
Hazards Radio waves are used to transmit information from one place to another through intervening media without wires. Radio and TV waves transmit: sound television signals, and data codes. Some claims suggest cell phone RFs may instigate brain tumors and even cancer. Exposures to RFs have been unofficially linked to sleep disorders, headaches, and other neurological problems. Uses/Benefits
http://www.arrl.org/how-antennas-work www.cellphonesaftey.org/health/radio.htm Works Cited
Microwaves Jake Epstein Robin Kovac Zach Sabol
Wave Characteristics • Transverse wave form • 10-1 – 10-3 meters • 109 - 1011 Hertz
Physical Comparison • One Dr. Grateful mole • Width of 3 Wilson Buffa Lou physics textbooks • Height of a dixie cup • Length of a finger X 3
Source • In space • Stars • On earth • Microwave ovens
Methods/How They Work • Detected by electronic or mechanical techniques • Frequency counters (heterodyne) • Mechanical – absorption wave meter
Uses/Benefits • Sensors in automatic doors • Heats food by dielectric heating • Spectroscopy • Can detect free radicals and transition metals
Hazards • Cannot cause ionization • Long-term exposure can have carcinogenic effects • High intensity exposure can cause burns • Radiation can create buzzing and clicking in auditory nerves
More Fun Stuff • NASA attempted to construct solar power satellites to give earth power via microwaves • Can be used to heat people up as a deterrent • Can be used in GPS navigation • Have been used to map the invisible surface of Venus
Bibliography "Microwaves." Microwaves. NASA, n.d. Web. 14 May 2013. WHO. "Electromagnetic Fields & Public Health: Microwave Ovens." WHO. WHO, Feb. 2005. Web. 14 May 2013. Wilson, Jerry D. Physics. Upper Saddle River, NJ: Pearson / Prentice-Hall, 2007. Print.
Infrared Light • Discovered by William Herschel in 1800 • IR not seen, but felt as warmth • Everything not at absolute zero emits IR • Transverse wave • Wavelength Range = 10-3 – 10-7 meters • Frequency Range = 1011 – 1014 Hz • Longer, far IR waves size of pin head • Shorter, near IR waves size of cells or microscopic
Infrared Light • Sun produces infrared light • Infrared pictures detect differences in temperature • assign different brightness or false colors to them • Not particularly harmful • not enough energy to start molecules moving, not enough to break them apart, or otherwise cause damage
Infrared Light • Uses • Night Vision = devices capture naturally emitted IR • Thermal Imaging = devices able to display outlines of the subjects based on the amount of infrared radiation • Communication = used to transfer data wirelessly • Astronomy = Infrared telescopes can either be used to detect the IR that are emitted by the celestial bodies themselves or the IR that is bounced off a cooler celestial body from a nearby star.
Bibliography "The Infrared." Infrared Waves. NASA, n.d. Web. 14 May 2013. Villanueva, John C. "Infrared Light." Universe Today RSS. N.p., n.d. Web. 14 May 2013. "What Is Infrared Light?" Infra Red Light. University of Chicago, n.d. Web. 14 May 2013.
Visible Light By Devon Riggs and Megan DelBianco
About the wave • Transverse wave • Wavelength Range: 700-400 nm • Frequency Range: 4.3x1014 to 7.5x1014 Hz
Similar Objects • The thickness of the membrane of a soap bubble is the same size as a wave of blue light
Sources and Detection Sources • The Sun • Stars • Light bulbs Detection • Cones in the eyes • Prisms to split light
Uses and Benefits • Colors can indicate temperature • Hotter is shorter wavelength (end of the rainbow) • Lasers are used in CD/DVD players and laser printers • Each element has absorption lines on a color spectrum • It can indicate the makeup of objects
Hazards • Too much or too bright visible light can be damaging to your retina • Visible light can cause objects to burn • Lasers can burn tissue and cause permanent damage to eyes
Interesting Information • Color blindness • Genetic disorder that is sex-linked • More common in males than females • Limits the colors in the spectrum that a person can see
Bibliography "The Electromagnetic Spectrum: Visible Light." The Electromagnetic Spectrum. N.p., n.d. Web. 14 May 2013. "Health Risks." Health Risks. N.p., n.d. Web. 14 May 2013. Shier, David, Jackie Butler, and Ricki Lewis. Hole's Human Anatomy & Physiology. Boston, MA: McGraw-Hill Higher Education, 2004. Print. "Visible Light." Mission:Science. NASA, 22 Mar. 2011. Web. 14 May 2013. Wilson, Jerry D. Physics. Upper Saddle River, NJ: Pearson / Prentice-Hall, 2007. Print.
Ultraviolet Light By: David Wilczynski, Dan Pomerantz, and Will Longworth
The UV Wave • Frequency Range: 10^14 Hz – 10^17 Hz • Wavelength: 10^-10 Hz – 10^-12 Hz • Transverse Object of Wavelength Size • (Between visible light and x-rays) • Large cell membrane
Sources Very hot bodies Stars (the sun) Special lamps on earth Hazards Skin cancer Sunburn Damage to corneas
Detection Methods • Silicon diodes • Photodiodesand photocathodes • Vacuum detectors • UV can propagate through a vacuum • Varies depending on place in spectrum
Benefits and Uses Vitamin D production Sterilization of contaminated objects Pest control Fire detection Fun Facts “Ultraviolet” = “beyond light” People without an eye lens can see UV light Ozone layer blocks 97% of UV light Bees can see UV light
By Natalie Guarna, ShainaShikoff, and Amanda Green X-RAY wAVES
General Information • Transverse • Wavelength Range: 10-10 to 10-12 m • Frequency Range: 1017 to 1019 Hz
Size Comparison A single atom 10-10 to 10-12 m
Sources • Stars • Some types of nebula • The sun • X-ray binaries
Detection Methods X-Ray Detectors: • Collect actual photons of x-ray light • Photographic film is ionized • Made of radiation-sensitive silver halide crystals • Photochemical change of affected crystals darkens the exposed area • X-rays can’t pass through calcium, so bones show up in images
Uses • Medical: x-ray machines, kill cancer cells • Security: airport (passenger and luggage) • Art History: to see if one picture is painted over another • X-ray diffraction: spectroscopy and crystallography (determining structure)
Hazards • Long term or frequent exposure causes damage to healthy body cells • Cancer
Fun Facts • Discovered by accident • German physicist W.C. Röntgen realized flourescent materials faintly glow when placed near a cathode-ray tube by a high voltage induction coil • Named for X meaning unknown
Bibliography "Light Tour." Cse.ssl.berkeley.edu. The Regents of the University of California, 2001. Web. 13 May 2013. Umland, Henning. "Some Facts about X-Rays." Celnav.de. Linux, n.d. Web. 13 May 2013.
X-rays Yinzi Xin
X-rays • Transverse electromagnetic waves • Wavelength range: 10-10 to 10-12 meters • About the size of an atom • Frequency range: 1017 to 1019 Hz
Where do they come from? • X-ray tubes – accelerates electrons and directs them toward a target to produce X-rays • Two processes: • Bremsstrahlung: energy level and bending of electron path used to manipulate wavelength of radiation produced • Characteristic X-rays: electron beam displaces target electrons in shells, replacement by another electron requires release of energy in the form of X-rays • Synchrotons – from charged particles crossing magnetic fields • In space – hot objects with vibrating atoms
How are they detected? • Photographic plates and films – variations in density provide a picture of what the X-rays are passing through
Uses • Medical applications – X-rays of bones to reveal damage • Computerized tomography – to produce three-dimensional images • Industry – to check for cracks and imperfections in products • Crystal research – crystollagraphy to determine structure and makeup of molecules • Astronomy – to detect temperatures of sources in outer space