Essential Questions
1. What are the Ultraviolet Rays?
2. How are these rays created?
3. What effect does these rays have on human society?
4. How are these rays measured?
2. How are these rays created?
3. What effect does these rays have on human society?
4. How are these rays measured?
Key Terms
UV Rays: Invisible rays that are part of the energy that comes from the sun. Ultraviolet radiation can burn the skin and cause skin cancer.
UVA: they are not absorbed by the ozone layer
UVB: the majority is absorbed by the ozone layer although some of it stays in terrestrial surface
UVC: it is completely absorbed by the ozone layer and oxygen
UVA: they are not absorbed by the ozone layer
UVB: the majority is absorbed by the ozone layer although some of it stays in terrestrial surface
UVC: it is completely absorbed by the ozone layer and oxygen
Unit Overview
-The sources of the ultraviolet waves are mostly stars, which includes the sun, that produces most of the radiation that strikes on earth
-The waves create a layer (9-19 miles above sea level), and the ozone layer absorbs almost all of it before it reaches earth and risks life
-If an ultraviolet wave takes lots of time penetrating the ozone layer, it causes sunburn and suntan
-The sun received from the rays can cause harm to the human body but it can also cause positive effects life the creation of vitamin D
-There are some artificial ultraviolet rays such as lamps because the glass protects you from the passage of the rays
-The impact of the UV Rays depend on the following factors:
*The Ozone Layer: it changes its effectiveness depending on the time of the year, and its currently being destroyed due to pollution
*The hour of the day: depending on the time, the UVB are higher and the solar rays on the atmosphere are shorter
*Time of the Year: it depends on the stations, which causes summer time to be stronger and higher risk
*Latitude/Altitude
-Effects on Humans:
*Skin Cancer, Lowers immune system, Cataracts, Rapid skin aging
-The waves create a layer (9-19 miles above sea level), and the ozone layer absorbs almost all of it before it reaches earth and risks life
-If an ultraviolet wave takes lots of time penetrating the ozone layer, it causes sunburn and suntan
-The sun received from the rays can cause harm to the human body but it can also cause positive effects life the creation of vitamin D
-There are some artificial ultraviolet rays such as lamps because the glass protects you from the passage of the rays
-The impact of the UV Rays depend on the following factors:
*The Ozone Layer: it changes its effectiveness depending on the time of the year, and its currently being destroyed due to pollution
*The hour of the day: depending on the time, the UVB are higher and the solar rays on the atmosphere are shorter
*Time of the Year: it depends on the stations, which causes summer time to be stronger and higher risk
*Latitude/Altitude
-Effects on Humans:
*Skin Cancer, Lowers immune system, Cataracts, Rapid skin aging
Dispositives & Gadgets
Mathematical Model
Amplitude: there is no specific amplitude (1 to -1)
Frequency: 7.5 x 10^14 to 3 x 10^17 Hz
Period: 400-320 nanometers
Kind of Graph: Sine-Cosine
Frequency: 7.5 x 10^14 to 3 x 10^17 Hz
Period: 400-320 nanometers
Kind of Graph: Sine-Cosine
Uses & History
Analytic Uses: forensics, electrical and electronic industry, florescent dye uses, analytic uses, sanitary compliance, chemistry
Material Science Uses: fire detection, photographically, polymers
Biology Related Uses: air purification, sterilization and disinfection, biological, therapy, herpetology
Discoveries: Mathematical Progress
-Discovered in 1801 by German physicist, Johann Wilhelm Rited
-John William Drapper discovered discovered that the ray came from light (tithonic rays)
-In 1878, the effect of short-waved length light on sterilizing bacteria was discovered
-In 1903, it was discovered that the most effective wave lengths were around 250nm
-In 1960, the effect of ultraviolet radiation on DNA was established
Material Science Uses: fire detection, photographically, polymers
Biology Related Uses: air purification, sterilization and disinfection, biological, therapy, herpetology
Discoveries: Mathematical Progress
-Discovered in 1801 by German physicist, Johann Wilhelm Rited
-John William Drapper discovered discovered that the ray came from light (tithonic rays)
-In 1878, the effect of short-waved length light on sterilizing bacteria was discovered
-In 1903, it was discovered that the most effective wave lengths were around 250nm
-In 1960, the effect of ultraviolet radiation on DNA was established
Multimedia
Real Examples
1. Used to sterilize medical equipment and some foods, emitted by the sun and can cause skin cancer and mutations in plants.
2. Stimulated the production of vitamin D in our body
3. Helps us when we hang washing outside to dry, as some of the bacteria present in the washing are inactivated by exposure to UVB.
4. Sun tan, detecting forged bank notes in shops, and hardening some types of dental filling.
5. Make glow
6. Kill Microbes
7. Food and drug companies also use UV lamps to sterilize their products.
2. Stimulated the production of vitamin D in our body
3. Helps us when we hang washing outside to dry, as some of the bacteria present in the washing are inactivated by exposure to UVB.
4. Sun tan, detecting forged bank notes in shops, and hardening some types of dental filling.
5. Make glow
6. Kill Microbes
7. Food and drug companies also use UV lamps to sterilize their products.