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Red colour is used for danger signals because

Red colour is used for danger signals because Correct Answer it undergoes least scattering

Explanation:

  • The dispersion of the light is inversely proportional to the fourth power of its wavelength.
    • Because red light has the largest wavelength of all colors, it is the least dispersed.
  • The red color is always used for danger signals because as red color is having the longest wavelength, it is the least scattered.

So, this signal can be seen from a very long distance.

Key Points

  • As the full spectrum of visible light travels through a prism, the wavelengths separate into the colors of the rainbow because each color is a different wavelength.

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  • Violet has the shortest wavelength, at around 380 nanometers, and red has the longest wavelength, at around 700 nanometers.

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