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Word of the week: Electromagnetic spectrum

8 Sep 2019, 10:15 UTC
Word of the week: Electromagnetic spectrum
(200 words excerpt, click title or image to see full post)

Color spectrum via Shutterstock.
When you think of light, you probably think of what your eyes can see. But the light to which our eyes are sensitive is just the beginning; it is a sliver of the total amount of light that surrounds us. The electromagnetic spectrum is the term used by scientists to describe the entire range of light that exists. From radio waves to gamma rays, most of the light in the universe is, in fact, invisible to us!
Light is a wave of alternating electric and magnetic fields. The propagation of light isn’t much different than waves crossing an ocean. Like any other wave, light has a few fundamental properties that describe it. One is its frequency, measured in Hertz, which counts the number of waves that pass by a point in one second. Another closely related property is wavelength: the distance from the peak of one wave to the peak of the next. These two attributes are inversely related. The larger the frequency, the smaller the wavelength – and vice versa.
You can remember the order of the colors in the visible spectrum with the mnemonic ROY G BV. Image via University of Tennessee.
The electromagnetic ...

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