Formation of a Rainbow (Essay Sample)

Formation of a Rainbow
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Formation of a Rainbow
A rainbow is a meteorological and an optical phenomenon that occurs as a result of both refraction and reflection of light in droplets of water suspended in the atmosphere (Buick, 2010). The spectrum of light that forms as a result of refraction and reflection of light appears as a multicolored bow. When viewed from the ground, the rainbow appears as a half circle with the red color at the top. Someone observing from the ground only sees the upper half of the whole circle since the remaining half of the whole rainbow is covered by the ground. An observer from a high point, such as a plane can see the rainbow as a full circle (Buick, 2010).
In the atmosphere, there are numerous water droplets that act as light refractor. The water droplets act as a medium for light refractor, though with a varied optical density compared to the adjacent air. Refraction occurs when waves of light cross the boundary of the medium (water droplets) to another (Buick, 2010). When the light waves enter the droplet, the speed of light decreases causing the path of light to bend. On reaching the edge of the water droplet an internal reflection occurs, followed by refraction outside the droplet. The double refraction and one reflection cause the light rays to be dispersed into a spectrum of colors (Thornes, 1999).
The light rays are composed of various light colors and each light color has a different angle of deviation. The angle at which the refracted light rays and the incoming light rays deviate is 42 degrees for the red light and 40 degrees for the blue light (Buick, 2010). The difference in the deviation angle is due to wavelengths. Blue light has a shorter wavelength than the red light; this makes it refract more light than the red light. The red light on the other hand refracts at a quite steeper angle compared to the blue light. There are several paths through which light can pass through in a water droplet and subsequently refract on the ground. These paths depend on either the location of the sun in relation to the incoming rays or the part of the droplets the incoming rays are in contact with (Buick, 2010). Most light rays deviate between 40 and 42 degrees. At these deviation angles, the light that is being dispersed is bright enough to form a spectrum of colors (ROYGBIV) that can be displayed in the sky.
The circular rainbow forms as a result of the presence of water droplets suspended in the atmosphere, and that are in...