MCQ

Red light is used as danger signal because it is:

  • A
    Accepted as symbol
  • B
    Pleasing to the eye
  • C
    Sensitive to the eye
  • D
    Has high wavelength

Answer

  1. Has high wavelength

Explanation:

Red light is used as danger signal because it is having high wavelength, less scattering ,hence can travel larger distances.

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