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प्रश्न
Give a scientific reason:
Danger signals are red in colour.
Give Reasons:
‘Danger’ signal lights are red in colour.
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उत्तर
- The effectiveness with which small particles scatter light depends on the size of the particles and the wavelength of the incident light.
- Red light has the longest wavelength and hence is scattered least by fog or smoke.
- Hence, red light can be clearly seen even from a distance.
- So, danger signal lights are usually red in colour.
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