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Power Waves

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

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  1. Power Waves 60 Hz 5X10^6 m

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. http://www.arrl.org/how-antennas-work www.cellphonesaftey.org/health/radio.htm Works Cited

  8. Microwaves Jake Epstein Robin Kovac Zach Sabol

  9. Wave Characteristics • Transverse wave form • 10-1 – 10-3 meters • 109 - 1011 Hertz

  10. 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

  11. Source • In space • Stars • On earth • Microwave ovens

  12. Methods/How They Work • Detected by electronic or mechanical techniques • Frequency counters (heterodyne) • Mechanical – absorption wave meter

  13. Uses/Benefits • Sensors in automatic doors • Heats food by dielectric heating • Spectroscopy • Can detect free radicals and transition metals

  14. 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

  15. 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

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 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.

  21. Visible Light By Devon Riggs and Megan DelBianco

  22. About the wave • Transverse wave • Wavelength Range: 700-400 nm • Frequency Range: 4.3x1014 to 7.5x1014 Hz

  23. Similar Objects • The thickness of the membrane of a soap bubble is the same size as a wave of blue light

  24. Sources and Detection Sources • The Sun • Stars • Light bulbs Detection • Cones in the eyes • Prisms to split light

  25. 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

  26. 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

  27. 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

  28. 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.

  29. Ultraviolet Light By: David Wilczynski, Dan Pomerantz, and Will Longworth

  30. 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

  31. Sources Very hot bodies Stars (the sun) Special lamps on earth Hazards Skin cancer Sunburn Damage to corneas

  32. Detection Methods • Silicon diodes • Photodiodesand photocathodes • Vacuum detectors • UV can propagate through a vacuum • Varies depending on place in spectrum

  33. 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

  34. By Natalie Guarna, ShainaShikoff, and Amanda Green X-RAY wAVES

  35. General Information • Transverse • Wavelength Range: 10-10 to 10-12 m • Frequency Range: 1017 to 1019 Hz

  36. Size Comparison A single atom 10-10 to 10-12 m

  37. Sources • Stars • Some types of nebula • The sun • X-ray binaries

  38. 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

  39. 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)

  40. Hazards • Long term or frequent exposure causes damage to healthy body cells • Cancer

  41. 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

  42. 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.

  43. X-rays Yinzi Xin

  44. 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

  45. 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

  46. How are they detected? • Photographic plates and films – variations in density provide a picture of what the X-rays are passing through

  47. 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

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