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STD 12 - 9. Ray optics abd optical instruments — NEET STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceNEETSTD 12 - 9. Ray optics abd optical instruments4 Marks
MCQ
In the formation of primary rainbow, the sunlight rays emerge at minimum deviation from rain-drop after
  • A
    One internal reflection and one refraction
  • ✓
    One internal reflection and two refractions
  • C
    Two internal reflections and one refraction
  • D
    Two internal reflections and two refractions
✓

Answer

Correct option: B.
One internal reflection and two refractions
b
Both the primary and secondary rainbows are phenomena that formed by the reflection and refraction of sunlight in tiny water droplets. Different colors of sunlight have different refractive index so they will be reflected in slightly different directions inside a water droplet and dispersed to form rainbow. The sunlight rays after being refracted twice and reflected once by the water droplet form a primary rainbow and emerge at minimum deviation.

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