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Give a scientific reason: Danger signal lights are red in colour. - Science

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प्रश्न

Give a scientific reason:

Danger signal lights are red in colour.

कारण बताइए
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उत्तर

  1. The effectiveness of scattering depends on the size of the particles and the wavelength of the light.
  2. Red light has the longest wavelength in the visible spectrum; therefore, it is scattered the least by air molecules, fog, or smoke.
  3. Due to minimal scattering, red light travels longer distances without losing its intensity and can be clearly seen from far away.
Therefore, danger signal lights are red in colour.
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2014-2015 (March)

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