Light: Visible & Invisible
When we look at the world around us, we see a dazzling array of colors, shapes and textures. But what we see is only a tiny fraction of the electromagnetic spectrum , the range of wavelengths that includes visible light, as well as radio waves, microwaves, infrared, ultraviolet, X-rays and gamma rays. Most of the e lectromagnetic spectrum is invisible to our eyes , and some of it can even pass through solid objects . Invisible light is the w avelengths in the electromagnetic spectrum too short or too long to be detected by the human eye. Visible light is the part of the electromagnetic spectrum that our eyes can detect. It consists of wavelengths from about 380 nanometers (nm) to about 740 nm. The percentage of the electromagnetic spectrum that the human eye can see is about 0.0035 percent. The colors that we perceive depend on the wavelength and intensity of the light. For example, red light has a longer wavelength and lower frequency than blue light, which has a shorter waveleng