Electromagnetic Energy/Spectrum/Waves/Radiation
- the terms light, electromagnetic waves, and electromagnetic radiation all refer to the same physical phenomenon: electromagnetic energy
- this energy can be described by:
- frequency
- wavelength
- energy
- all three are related mathematically such that if you know one, you can calculate the other two:
- the following 3 are scientific conventions that allow the convenient use of units that have numbers that are neither too large nor too small
- radio and microwaves are usually described in terms of frequency (Hertz)
- infrared and visible light in terms of wavelength (meters)
- x-rays and gamma rays in terms of energy (electron volts)
Electromagnetic Spectrum
|
Category |
Range of Wavelengths (nm) |
Range of Frequencies (Hz) | |
|
< 3x109 | ||
|
Microwave |
105 - 108 |
3x109- 3x1012 | |
|
Infrared |
700 - 105 |
3x1012- 4,3x1014 | |
|
400 - 700 |
4,3x1014- 7,5x1014 | ||
|
Ultraviolet |
10 - 400 |
7,5*1014- 3x1016 | |
|
X-ray |
1 - 10 |
3x1016- 3x1017 | |
|
Gamma Ray |
< 1 |
|