Ultraviolet Radiation

a form of radiation that occurs beyond the violet end of the visible light spectrum of ELECTROMAGNETIC WAVES. Ultraviolet rays have a FREQUENCY ranging from 10¹⁵Hz to 10¹⁸Hz, with a wavelength from 10^-7m to 10^-10m. They are part of natural sunlight and are also emitted by white-hot objects (as opposed to red-hot objects, which emit INFRARED RADIATION). As well as affecting photographic film and causing certain minerals to fluoresce, ultraviolet radiation will rapidly destroy bacteria. Although ultraviolet rays in sunlight will convert steroids in human skin to vitamin D (essential for healthy bone growth), too much can cause irreversible damage to the skin and eyes and damage the structure of the DNA in cells. Fortunately, a great deal of the ultraviolet radiation from the sun is prevented from reaching the earth as the OZONE LAYER in the upper atmosphere acts as a UV filter.

Taken from Dictionary of Science

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The discovery of UV radiation was intimately associated with the observation that silver salts darken when exposed to sunlight. In 1801 the German physicist Johann Wilhelm Ritter made the hallmark observation that invisible rays just beyond the violet end of the visible spectrum were especially effective at darkening silver chloride-soaked paper. He called them "de-oxidizing rays" to emphasize their chemical reactivity and to distinguish them from "heat rays" at the other end of the visible spectrum. The simpler term "chemical rays" was adopted shortly thereafter, and it remained popular throughout the 19th century. The terms chemical and heat rays were eventually dropped in favor of ultraviolet and infrared radiation, respectively.

The discovery of the ultraviolet radiation below 200 nm, named vacuum ultraviolet because it is strongly absorbed by air, was made in 1893 by the German physicist Victor Schumann.

Taken from Wikipedia

I have classmates who ask to copy my homework, but I'm scared to tell them no. I guess you can say that I'm scared of them. What should I do?

A. If you let them cheat by giving them your homework, you will end up with more trouble than if you didn't. Word will get quickly around that you are a source to copy homework from.

Dishonest classmates will start relying on you for finished assignments when theirs aren't done. You will encourage them not to do their work because they can always get it from you. They won't be learning anything and will be hurt in the long run.

Don't allow them to intimidate you. You might get caught and be punished for helping them cheat. More important, you would be doing something you know is wrong and would be tearing down character.

A solution is to offer to help those who might ask you about copying your homework. Show them how to get the answers or where to find them in the book.

It's best to maintain your integrity and reputation. Eventually your classmates will respect you and may even ask for help.

Honesty is the best policy. To cheat or to condone cheating will only hurt everyone.

- Answer prepared by Victor Kubik, a minister of the Worldwide Church of God

Taken from Youth 90 magazine