True ultraviolet (UV) light is a form of electromagnetic radiation, specifically characterized by its wavelength.
Understanding UV Light
- Definition: UV light is a type of electromagnetic radiation with wavelengths ranging from 10 to 400 nanometers.
- Position in the Spectrum: It sits on the electromagnetic spectrum between visible light and X-rays. This means its wavelengths are shorter than those of visible light but longer than those of X-rays.
Key Characteristics
- Wavelength: The defining characteristic of UV light is its wavelength, which falls within the 10–400 nm range.
- Energy: Due to its shorter wavelength, UV light carries more energy than visible light.
- Invisibility: UV light is invisible to the human eye; however, some insects, like bees, can see certain types of UV light.
Subcategories of UV Light
UV light is often divided into three subcategories:
-
UVA (315-400 nm):
- Longer wavelength UV light.
- Reaches the Earth's surface in large quantities.
- Contributes to tanning and skin aging.
-
UVB (280-315 nm):
- Medium wavelength UV light.
- Mostly absorbed by the ozone layer.
- Can cause sunburn and increase skin cancer risk.
-
UVC (100-280 nm):
- Shortest wavelength UV light.
- Completely absorbed by the atmosphere.
- Has germicidal properties (used for sterilization).
Practical Insights
- Sunlight: The sun is the primary source of UV light.
- Artificial Sources: UV light is also produced by artificial sources such as tanning beds, certain types of lamps, and lasers.
- Applications: UV light has many applications, including sterilization, water purification, medical treatments, and scientific research.
Summary
Feature | Description |
---|---|
Type | Electromagnetic radiation |
Wavelength Range | 10-400 nanometers |
Location | Between visible light and X-rays |
Visibility | Invisible to human eyes |
Energy | Higher than visible light |
In conclusion, UV light is electromagnetic radiation with wavelengths of 10–400 nanometers, positioned between visible light and X-rays.