By Ally Loker
What are two ways that EM waves are different from mechanical waves?
What type of disturbance creates a EM wave?
The Electromagnetic Spectrum
This portion of the electromagnetic spectrum, called visible light is the light and colors visable to the human eye. Our eyes can only see this small portion of the spectrum. For example rainbows and fireflies are some of the things the human eye is able to see.
Wavelength (m) : 4 x 10-7 - 7 x 10-7
Frequency (Hz) : 4 x 1014 - 7.5 x 1014
Energy (J) : 3 x 10-19 - 5 x 10-19
X-rays are commonly used in doctors offices, dentists, and even by airport secuirty. An x-ray allows for the contents or insides of an object or body to be visable without removing the outer protection.
Wavelength (m) : 1 x 10-11 - 1 x 10-8
Frequency (Hz) : 3 x 1016 - 3 x 1019
Energy (J) : 2 x 10-17 - 2 x 10-14
Gamma rays are created by nuclear reactions and are extremely useful for those in need of cancer treatmnet. Gamma rays are used in chemotherapy to kill the cancer cells. thus making it a very important part of the spectrum.
Wavelength (m) : < 1 x 10-11
Frequency (Hz) : > 3 x 1019
Energy (J) : > 2 x 10-14