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प्रश्न
Give a scientific reason:
Danger signal lights are red in colour.
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उत्तर
- The effectiveness of scattering depends on the size of the particles and the wavelength of the light.
- Red light has the longest wavelength in the visible spectrum; therefore, it is scattered the least by air molecules, fog, or smoke.
- Due to minimal scattering, red light travels longer distances without losing its intensity and can be clearly seen from far away.
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संबंधित प्रश्न
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\[\mu = 1 \cdot 5\]. Both the side are convex. It is dipped in water \[\mu = 1 \cdot 33\]. It will behave like
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Locate the image of the point P as seen by the eye in the figure.
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| Case study: Mirage in deserts |
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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: |
Which of the following phenomena is prominently involved in the formation of mirage in deserts?
The sky would appear red instead of blue if
A passenger in an aeroplane shall ______.
