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Why Does the Sun Look Reddish at Sunset Or Sunrise ? - Physics

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प्रश्न

Why does the Sun look reddish at sunset or sunrise ?

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उत्तर

At the time of sunset or sunrise, the Sun and its surroundings appear red because of the scattering of light. At the time of sunset or sunrise, the light rays from the Sun have to travel a long distance to reach our eyes through the Earth's atmosphere. In other words, we can say that when we look towards horizon, we are looking through more of Earth’s atmosphere than when we look overhead. The light reaching our eyes is rich in red colour as blue light is largely scattered away by the particles present in the Earth's atmosphere.

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2014-2015 (March) Foreign Set 2

संबंधित प्रश्‍न

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Case study: Mirage in deserts

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Based on the above facts, answer the following question :

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Case study: Mirage in deserts

To a distant observer, the light appears to be coming from somewhere below the ground. The observer naturally assumes that light is being reflected from the ground, say, by a pool of water near the tall object.

Such inverted images of distant tall objects cause an optical illusion to the observer. This phenomenon is called mirage. This type of mirage is especially common in hot deserts.

Based on the above facts, answer the following question:

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A short pulse of white light is incident from air to a glass slab at normal incidence. After travelling through the slab, the first colour to emerge is ______.


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