For example, blue has a short wavelength, while red is created by longer wavelengths. Light that looks white to us, is actually made up of many different colours of differing wavelengths. Light travels from the Sun and through the atmosphere in invisible waves. This is shown in the diagram below (click to enlarge).To begin, we need to understand how we see colour. This light can scatter to the side and remain vertically polarized, but it cannot scatter upward! To retain the characteristic of a transverse wave after scattering, only the vertically polarized light can be scattered sideways, and only the horizontally polarized light can be scattered upward. Consider only the vertically polarized light passing through the tank. The beam of light contains photons of light that are polarized in all directions-horizontally, vertically, and all angles in between. The direction of the transverse oscillation of the electric field is called the direction of polarization of light. Scattering polarizes light because light is a transverse wave. When the two polarizations are aligned, the beam will be bright when they are at right angles, the beam will be dim. The filter and the scattering polarize the light.
You can also hold the polarizing filter between your eyes and the tank and rotate the filter to make the beam look bright or dim. Notice that when the person looking down from the top sees a bright beam, the person looking in from the side will see a dim beam, and vice versa. Turn the filter while one person views the transmitted beam from the top and another views it from the side. Place a polarizing filter between the flashlight and the tank. The sun puts out much more blue light than violet light, so most of the scattered light in the sky is blue. So why isn’t the sky violet? Because there’s just not enough of it. Violet light has an even shorter wavelength than blue light: It scatters even more than blue light does. The light you finally see is reddish orange. By the time the light of the setting sun reaches your eyes, most of the colors of light have been scattered out. Why does the setting sun look reddish orange? When the sun is on the horizon, its light takes a longer path through the atmosphere to your eyes than when the sun is directly overhead. When you look up in the sky, the scattered blue light is the light that you see. The red light that is not scattered continues on in its original direction. Blue light pushes on the electrons with a frequency that is close to their natural resonant frequency, which causes the blue light to be re-radiated out in all directions in a process called scattering. That is, if the electrons bound to molecules in the air are pushed, they will oscillate with a natural frequency that is even higher than the frequency of blue light. In addition, the frequency of blue light, compared to red light, is closer to the resonant frequency of the atoms and molecules that make up the air. Because its wavelength is so much shorter, blue light is scattered approximately ten times more than red light. The shorter the wavelength of the light, the more it is scattered by the atmosphere. When the white light from the sun shines through the earth’s atmosphere, it collides with gas molecules. The colors in the rainbow spectrum are arranged according to their frequencies: Violet and blue light have higher frequencies than yellow, orange, and red light. Light is a wave, and each of these colors corresponds to a different frequency and therefore a different wavelength of light. The sun produces white light, which is made up of light of all colors: red, orange, yellow, green, blue, and violet.
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