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