Ultraviolet Rays By Julian Lawrence and Justin Piselli

Facts About UV UV rays are between visible light and x- rays in the Electromagnetic Spectrum Wavelengths between 100 nanometers and 400 nanometers Frequencies between Terahertz and Terahertz

Uses and Applications of UV Helps our bodies in making vitamin D Helps our bodies build immunities to diseases such as Rickets (bone disease) and colon cancer UV watermarks view personal info on credit cards, driver licenses, and passports

Who Can See It/Sense It Humans cannot see UV, but they can feel it (sunburn) Butterflies and bees have evolved to see it, but the reasons are unknown

Is UV Harmful UV rays can burn the eyes, hair, and skin if body is not properly protected UV rays are most powerful at noon, worst time to be outside

Discovery of UV Rays William Herschel and Johann W. Ritter discovered that there were regions of light invisible to the naked eye. Ritter discovered electromagnetic emissions in region beyond violet end of visible spectrum. He discovered that silver chloride darkened when exposed to visible light and even more beyond “Violet” end of the spectrum Both discoverers concluded that the source of UV rays comes from the sun

Two Discoverers William HerschelJohann W.Ritter

Bibliography "Student's Guide - Ultraviolet Radiation." Welcome to Biospherical Instruments Inc. Web. 27 Apr < "What Are UV Rays?" WiseGEEK: Clear Answers for Common Questions. Web. 04 May Discovery of Ultraviolet & Infra Red Radiation." Medindia - Medical / Health Website. Web. 04 May