Physics Period 7 Joshlyn Brown
Electromagtnetic Wave : Ultraviolet Light
Wavelength of Ultraviolet Light :
Frequency Range for Ultraviolet Light
-Ultraviolet (UV) light falls in the range of the EM spectrum between visible light and X-rays. It has frequencies of about 8 × 10^14 to 3 × 10^16 cycles per second, or hertz (Hz), and wavelengths of about 380 nanometers (1.5 × 10^-5 inches) to about 10 nm (4 × 10^-7 inches).
1. Apple juice or cider is treated with UV light to reduce the levels of microbial pathogens.
2. Many birds have patterns in their plumage that are invisible at usual wavelengths but observable in ultraviolet and the urine and other secretions of some animals, including dogs, cats, and human beings, is much easier to spot with ultraviolet.
3. UV light has been proven for decades to effectively disinfect air, surfaces and water.
4. Ultraviolet levels are over 1,000 times higher at the equator than at the polar regions so it is presumed that marine life at the equator are much better adapted to the higher environmental UV light than organisms in the polar regions.
5. Scientists have divided the ultraviolet part of the spectrum into three regions: the near ultraviolet, the far ultraviolet, and the extreme ultraviolet.
Everyday Applications for Ultraviolet Light:
1. Tanning Beds
2. Bug Zappers
Health Impacts for Ultraviolet Lights: ( Positive and Negative)
Positives: UV from the Sun is needed by our bodies to produce vitamin D. Vitamin D helps strengthen bones, muscles and the body’s immune system. It may also lower the risk of getting some kinds of cancers such a colon cancer. And it also disinfection and sterilization all kinds of things.
Negatives: UV burns the skin. Sunburn is a burn that occurs when skin cells are damaged. This damage to the skin is caused by the absorption of energy from UV rays. Extra blood flows to the damaged skin in an attempt to repair it, which is why your skin turns red when you are sunburned. And it also damages eyes and ages the skin.