Question

why the danger signals are red in colour ​

Answer 1

Answer:

Red colour is always used for danger signals, because as red colour is having the longest wavelength, it is the least scattered. So, this signal can be seen from a very long distance.

Explanation:

Answer 2

Answer:

When the light passes through atmosphere, it gets scattered by small air particles. The scattering of light is inversely proportional to the fourth power of its wavelength. As the red light has the highest wavelength among all the colours, so it is scattered the least. Due to which most of the light gets reflected back and can travel longer distances through rain, fog, dust etc. to reach our eyes effectively.

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