The danger signal is red. Why? - Noon Academy

The danger signal is red. Why?

Class 10 | ICSE | Physics | Selina | Spectrum

The danger signal is red. Why?

In visible light, red light has the longest wavelength. As a result, red-colored light is dispersed the least by air molecules in the environment. As a result, when compared to other colours, red light may travel a greater distance. In comparison to light of other colours of same intensity, red light may be perceived from the greatest distance. As a result, red light is utilised for warning signals so that they may be seen from a long distance, especially in foggy conditions.

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