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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
When light emitted by a white hot solid is passed through a sodium flame, the spectrum of the emergent light will show
  • A
    The ${D_1}$ and ${D_2}$ bright yellow lines of sodium
  • ✓
    Two dark lines in the yellow region
  • C
    All colours from violet to red
  • D
    No colours at all
✓

Answer

Correct option: B.
Two dark lines in the yellow region
b
When light emitted by a white hot solid passes through sodium vapour then cooler sodium vapour absorb energy from white light spectrum producing spectrum of bright yellow light with two dark lines in the yellow region.

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