Why is the red colour selected for danger signal lights?
WBBSE
Class X
Physical Science
Light – Reflection and Refraction
02 Mark
2025
Red colour is selected for danger signal lights because it has the longest wavelength and is scattered the least by the particles present in the atmosphere.
As a result, red light can travel a greater distance and remains clearly visible even in fog, mist, smoke, or dust. Therefore, it is used for danger signals, traffic lights, and stop signals.
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