what is a mirage?

Question

once i was coming from bike at a 100m dist from the road.i was able to see the water on the road.but when as i came nearer to that place water was'nt there.i thought it was illusion .i want to know what is the reason for the illusion?

Answer 1

Mirage is a real image caused by refraction (bending) of light rays. Repeat it is an image, but not a concrete object and therefore, can be seen but not touched... because it is light. It is the refracted light from a distant object, commonly the sky or a body of water. That is the reason why when you get nearer to it, it is not there. Mirage is not an optical illusion because as I've said it is actually there, but the visual interpretation differs with the observers...

Answer 2

A mirage is a naturally-occurring optical phenomenon, in which light rays are bent to produce a displaced image of distant objects or the sky. The word comes to English via the French mirage, from the Latin mirare, meaning 'to appear, to seem'. This is the same root as for mirror. Like a mirror, a mirage shows images of things which are elsewhere. The principal physical cause of a mirage, however, is refraction and not reflection.

A mirage is not an optical illusion. It is a real phenomenon, and one can take photographs of it. The interpretation of the image, however, is up to the fantasy of the human mind.

Cause-

The cause of an inferior mirage (light curvature strongly exaggerated)Cold air is denser than warm air, and has therefore a greater refractive index. As light passes from colder air to warmer air it bends away from the direction of the temperature gradient (the "normal" in the figure at right); when it passes from hotter to colder, it bends towards the direction of the gradient. The diagram on the right shows a light ray coming from the sky toward the hot ground. If the air near the ground is warmer than that higher up, the light ray bends in a concave upwards trajectory. Once the ray reaches the viewer’s eye, the eye traces it as the line of sight, which is the line tangent to the path the ray takes at the point it reaches the eye. The result is that an inferior image for the above sky appears on the ground. The viewer may incorrectly interpret this sight as water reflecting the sky. In the case where the air near the ground is cooler than that higher up, the light rays will of course curve downwards, producing a superior image.

The 'rest' state of the Earth's atmosphere is with a vertical gradient of about -1 degree Celsius per 100 metres height. (The value is negative because it gets colder when you go higher.) For an actual mirage to happen, the temperature gradient has to be much greater. According to Minnaert the magnitude of the gradient should be at least 2°C per metre, and the mirage will not get strong until the magnitude reaches 4 or 5°C per metre. These conditions can occur when there is strong heating at ground level, for example when the sun is shining on sand or asphalt..

Answer 3

It wasn't an illusion it was a reflection that was distorted by the rising heated air that was produced by the hot ground.
A mirage is a reflection of a distant object that is lensed and magnified by the intervening air and could be many miles away and out of sight.

Answer 4

Mirage is an optical illusion that normally occurs in hot areas due to total internal reflection..

Answer 5

- First:
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What is meant by Mirage ??
It is a natural phemomenon that takes place in desert or on a paved road at noon where the image of far object appears as if reflected on the surface of the paved road that seems to be wet

- Second:
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How it produced ??
In hot days, the temprature of air layers increases as it gets closer to Earth's surface, so their optical density decreases (i.e. the refractive index of air layers decreases)
Therfore: The light rays transfere from the upper layers to the lower ones refract successivelly away from the normal (perpendicular) untill the angle of incidence is bigger than the critical angle
Therfore: Total internal reflection takes place & the eye sees the object along the extension of reflected rays as if it is reflected on the surface of water

i hope u got my explanation

Answer 6

Mirage is a kind of optically illusion caused due to refraction (Bending) of light.The water which you saw was the reflexion of the blue sky.

Answer 7

You know the reason then why to ask. Mirage occurs due to total internal reflection. It is a natural phenomenon. If you wanna know in detail, i could suggest some good sites.

Answer 8

beacuse when we see water ahead of us in roads but in actually after reaching that place we find no water their it is called mirrage. and it is happen due to toal internal reflection of light by atmospheris refraction upward . total internal reflection of light means when light pasees from an optically deser to rarer medium for ex water or galss to air

Answer 9

mirage is formed due to total internal refraction

Answer 10

Its an illusion .... that can be seen only at a distance ...

most commonly seen on roads...

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