Why does a rainbow appear bent or arched in a semicircle in the sky?
Rainbows Rainbows have been the subject of songs and poems, stories and mythology, but there is an explanation as to why rainbows appear as they do. Rainbows are light and you can't touch them. The sun must be shining and must be behind you, and there must be water droplets in the air in front of you. Sunlight shines into the water drops which act as tiny prisms that bend or "refract" the light and separate it into colors. Rays of a rainbow bend twice. As they enter the drops, the rays are bent, then they reflect off the back of the drops and bend again as they exit out the front of the drops. The rainbow is circular because when a raindrop bends light, the light exits the raindrop at a 40-42 degree angle away from the angle it entered the raindrop. The violets and blues bend at a 40 degree angle, and the oranges and reds bend at a 42 degree angle. Light can also enter droplet, be reflected off the back of the droplet, only to be reflected of the front, and then off the back again before leaving. It is bent at each phase in this process, and a second rainbow can appear above the first one. In a double rainbow, the second rainbow will appear where it does because the light will be cumulatively bent some 50 to 53 degrees. This gives it its position "outside" the primary rainbow. Also, the colors will be inverted in this bow. Rainbows don't have "ends" but are full circled, but we can't see this because the horizon of the earth is in the way. If the sun is very low in the sky, either just before sunset or just after sunrise, we can see a half circle. The higher the sun is in the sky, the less we see of the rainbow. The only way to see the full circle of a rainbow in the sky is to be above the ground and have the sun behind you. You would have to look out on the drops from an airplane to see a circular rainbow. Now, this is quite complex, so it's possible you might get away with the old standard, "There is gold at the end of the rainbow and that's what makes the colors." Be sure that you watch your 6-year old closely as he/she might decide to pack his/her bags and go hunting for that bag of gold! Another way you may get away with explaining this off is buying a "prism" (it's a glass drop) and hanging it in a sunny window. It will reflect beautiful spots of light in the room and the effects are quite pleasant to study. Another way to view a full rainbow without leaving the ground is using a garden hose. Have it spray water in bright sunlight with the sun behind you and the spray in front of you. If the entire circle is not visible you can move the hose around to see the rest of the circle. The ones seen from airplanes are more spectacular, though.
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Answer . A rainbow is a circle if viewed from the air, and it is sometimes not even that, if it is faint enough
Because rainbow is illusion of eyes. It is cause of sun rayshitting water or moist. Rays curve up after hitting rain drops.
A rainbow just appears as a semicircle but it is actually a complete circle. We just don't see the whole thing because the horizon gets in the way. Sometimes people on planes …will see the entire circle with the shadow of the plane in the center. White light is made up of a mixture of all the different colors. Light takes the form of waves and all the different colors have a different wavelength. Red light has the longest wavelength (720 nm) while violet has the shortest (380 nm). These different wavelengths can be used to explain why you see all the different colors in the rainbow. When light hits water droplets in the air, it is bent slightly - this bending is called diffraction. The amount of diffraction depends on the wavelength - Red light is bent less than blue light so when white light meets the water droplets, it is separated into all the different colors. If you turn on a garden hose, adjust the nozzle to a fine spray and stand with your back to the sun, you will see a rainbow shining in the spray!
Apparently, a rainbow appears in the sky because both, rain and sun, mix together and produce light and colours. Some people belive that at the end of a rainbow is gold. But h…ow does the gold just appear suddenly?
A rainbow or louds lolol
A rainbow is a portion of a circle. It represents an angle betweenthe line Sun-to-back-of-your-head, and the angle of total internalreflection of each wavelength in the raindr…ops. Its an opticalillusion. As the light passes thought the moisture in the sky itsrefracted causing the light to change it direction as the lightleave the droplets its does so at differing angles theseangles.These different colors of light have all slightly differentdirections and so display each color components of white light.Thus, the angle of bending is different for different wavelengthsof light. This band of colors appears in the same pattern as thecolors of a rainbow. This means, all the different colors of light(red, orange, yellow, green, blue, indigo and violet) combine togive you what is called white light You can see circular rainbows sometimes when viewing them fromaircraft or high mountain tops where the full area needed toproduce a visible circular rainbow has enough droplets. The rainbow's appearance is caused by dispersion of sunlight as itis refracted by (approximately spherical) raindrops. The light isfirst refracted as it enters the surface of the raindrop, reflectedoff the back of the drop, and again refracted as it leaves thedrop. The overall effect is that the incoming light is reflectedback over a wide range of angles, with the most intense light at anangle of about 40-42 degrees. The different colors (wavelengths) oflight have different refractive indices which cause them to bendunequally. Thus, a rainbow is arc-shaped. We don't actually see the full circle because the earth gets in theway. The closer the sun is to the horizon, the more of the circlewe see. Right at sunset, we would see a full semicircle of arainbow with the top of the arch 42 degrees above the horizon. Thehigher the sun is in the sky, the less of a rainbow is visibleabove the horizon.
\nRed has lower energy and blue has higher so they are refracted less. Think of cars. One is going faster so it goes farther when it hits water. Cars with less energy will not… go farther, and will be refracted more
A rainbow is actually round. On the ground, the bottom part is hidden. In the sky, like from the view of a flying airplane, it can be seen as a round shape. Check the Popsc…i link for more information.
becaz the critical angle of rainbow is so large......
A rainbow is a natural prismatic phenom. White light, containing all colors, strikes water particles in mid-air. Just like with a prism, the light must pass thru the moisture …and as it does, the light is broken down into it's different wavelengths. They are represented in order of speed from which they pass thru the moisture. The wavelengths and speed at which each respective color of light passes thru the moisture does not change, so therefore, every rainbow is always comprised of the same colors and displayed in the same order.
Nothing. Although i thought that same thing too. But no. Nothing happens.
They're reminded of the passage in the old testament, translated from the Hebrew Torah, where the appearance of a rainbow is designated as a reminder of the promise that the… world will never again be destroyed by flood.
Because AT the location of every water droplet inthe air, the angle between the direction to the sun and the direction to your eye must be the same. The only shape in which …that's possible at every point is a circle.
Because at every point IN the rainbow, the angle between thedirection to the sun and the direction to your eye has to be the same angle. Theonly bunch of points that can satis…fy that requirement is a bunch ofpoints that are all on the same circle.
The sun refleing off the water