A bit complicated? Following the explanation with a paper cone in your hand might help! Colin Gauld, Kiama Downs Because they are weighed down by the pots of gold at the ends. Barrie Brown, Gordon. Because if they were straight you would never be able to get the pot of gold at the end.
Sam Duddy, Wollongong We see the shape of a rainbow as a curve because we are looking at it from a globe, and the light adjusts to the shape of the planet. Alice Russo, Paddington A rainbow is formed when sunlight is reflected from droplets of water in the atmosphere back towards you. Each water droplet acts like a tiny glass prism, bending the light that enters so that it exits at a different angle. Hence you can only see the reflected light if this angular difference matches the angle between you, the water droplet and the sun.
The angle is fixed by the properties of air and water, so that you see a band of reflected light forming a semicircle with a radius of about 42 degrees. The angle is slightly different for different colours of light, which is why the band appears coloured. Unfortunately, the fixed angle between you and each end of the rainbow means you can never reach one end to find that elusive pot of gold.
David Roche, Helensburgh All rainbows start out straight. They become curved or bent under the weight of two pots of gold, one at each end of the rainbow. As to why leprechauns hang them there, that is another big question. Ralph Gyoery, Chatswood Rainbows are formed by faraway drops of water reflecting and bending sunlight.
The sunlight takes a complicated path through each water droplet. It comes in the side closest to the sun and then bends as it passes through the water droplet, bounces off the back surface of the droplet, travels back to the other side, and bends once again on its way out. Only those water droplets that have the same angle formed by you, the drop, and the sun approx 42 degrees will contribute to the rainbow. The rainbow appears curved because the combined set of all these angles lies on a horizontal cone pointing at the sun with you at one tip.
Now light from the sun is a mixture of different colours or wavelengths - red, yellow, green, blue, violet - that look white when they are superimposed. The water droplet's density bends each colour's light path slightly differently which means the colours now appear split and visible. This is what gives the rainbow its distinctive colour separation. David Buley, Seaforth Firstly, there is a lot more to a rainbow than meets the eye.
Its longitudinal centre is located on the line between the sun behind you and the centre of your vision. To view the same rainbow a bystander would have look through the back of your head at eye level. Your rainbow is unique Now why are rainbows curved? They are not only curved but are part of a circle. If you are high enough, say in an aeroplane, and the sun is low enough behind you, you will see a complete circle. We only see the upper section when at ground level.
Particles of water occurring in a down-sun rainfall cause the suns rays to refract and they split into the familiar colour bands. Remember the prism in junior school. Have enough of these particles occurring in sequence and the light paths scatter all over the place. You see the ones that are eventually directed back along your sight path. Accepted light transmission physics embraces a concept of wave formation and particle photon travel.
We select the most convenient one; wave pattern. The light receptor, in your case the human eye, is attuned to the amplitude of the wave. Now a specific point of amplitude locates a precise point along the wave length which is a measure of distance - in this case from to the rainbow to you. So every part of your rainbow that you see is equidistant from you.
Look through a leftover tube from your cling-film supply. The distance from your eye to the far edge is the same at all points and the far edge is circular. So is your rainbow. Tim Bowra, Rozelle.
Why do dogs have wet noses? The wet nose helps cool dogs off, as they don't have sweat glands and can lose moisture only through the pads of their feet. Jaya Seethamraju, Gladesville. Why are do dogs have wet noses: Why are human noses dry when cats, bears, weasels, shrews, koalas and most other animals have wet noses? Elizabeth Latimer Hill, Denistone Well, the answer I like is because when Noah's Ark developed a leak, the hole was plugged by the nose of one of the dogs on board.
That is why dogs' noses are always wet and cold! Mary Milton, Kenthurst. Guessing that sea salt comes from the sea, where does table salt come from? Table salt is scooped off the top of the water table. Adrian Cooper, Queens Park. These are tight circles that can appear around the antisolar point when you're staring downward at a cloud or a blanket of fog. Unlike rainbows, they're the product of electromagnetic waves.
It's possible to see glories from tall mountain peaks. Also noteworthy are the multicolored halos that sometimes encircle the sun or moon. The eerie rings are made by the interaction of light and suspended ice crystals. A bridge that runs through Jim Henson's childhood hometown of Leland, Mississippi, has been officially named " The Rainbow Connection Bridge " in his honor. If you don't get the reference, "Rainbow Connection" is the name of an Oscar-nominated ballad sung by Kermit the Frog — Henson's most popular character — in 's "The Muppet Movie".
Sign up for our Newsletter! Mobile Newsletter banner close. Mobile Newsletter chat close. Mobile Newsletter chat dots. Mobile Newsletter chat avatar. Mobile Newsletter chat subscribe. Forces of Nature. Atmospheric Science.
The majority of rainbows we see look like arches, because they are partly blocked by the ground and horizon. In reality, all rainbows are complete circles, like this one photographed over Gorssel, Netherlands.
Cite This! Try Our Crossword Puzzle! What Is the Missing Number? Try Our Sudoku Puzzles! More Awesome Stuff. Rainbows are the result of the refraction and reflection of light.
Both refraction and reflection are phenomena that involve a change in a wave 's direction. A refracted wave may appear "bent", while a reflected wave might seem to "bounce back" from a surface or other wavefront. Light entering a water droplet is refracted. It is then reflected by the back of the droplet.
As this reflected light leaves the droplet, it is refracted again, at multiple angles. The radius of a rainbow is determined by the water droplets' refractive index. A refractive index is the measure of how much a ray of light refracts bends as it passes from one medium to another—from air to water, for example. A droplet with a high refractive index will help produce a rainbow with a smaller radius.
Saltwater has a higher refractive index than freshwater, for instance, so rainbows formed by sea spray will be smaller than rainbows formed by rain. Rainbows are actually full circles. The antisolar point is the center of the circle. Viewers in aircraft can sometimes see these circular rainbows.
Viewers on the ground can only see the light reflected by raindrops above the horizon. Because each person's horizon is a little different, no one actually sees a full rainbow from the ground. In fact, no one sees the same rainbow—each person has a different antisolar point, each person has a different horizon.
Someone who appears below or near the "end" of a rainbow to one viewer will see another rainbow, extending from his or her own horizon. A rainbow shows up as a spectrum of light: a band of familiar colors that include red, orange, yellow, green, blue, and violet. The name " Roy G. Biv " is an easy way to remember the colors of the rainbow, and the order in which they appear: red, orange, yellow, green, blue, indigo, and violet.
Many scientists, however, think " indigo " is too close to blue to be truly distinguishable. White light is how our eyes perceive all the colors of the rainbow mixed together. Sunlight appears white. When sunlight hits a rain droplet, some of the light is reflected. The electromagnetic spectrum is made of light with many different wavelength s, and each is reflected at a different angle.
Thus, spectrum is separated, producing a rainbow. Red has the longest wavelength of visible light, about nanometer s. It usually appears on the outer part of a rainbow's arch. Violet has the shortest wavelength about nanometers and it usually appears on the inner arch of the rainbow. At their edges, the colors of a rainbow actually overlap.
This produces a sheen of "white" light, making the inside of a rainbow much brighter than the outside. Visible light is only part of a rainbow. Infrared radiation exists just beyond visible red light, while ultraviolet is just beyond violet. There are also radio wave s beyond infrared , x-ray s beyond ultraviolet , and gamma radiation beyond x-rays.
Scientists use an instrument called a spectrometer to study these invisible parts of the rainbow. The atmosphere opposite a rainbow, facing the sun, is often glowing. This glow appears when rain or drizzle is falling between the viewer and the sun. The glow is formed by light passing through raindrops, not reflected by them. Some scientists call this glow a zero-order glow. Sometimes, a viewer may see a "double rainbow.
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