MCQ
Line spectrum was first of all theoretically explained by
  • A
    Swan
  • B
    Fraunhofer
  • C
    Kirchoff
  • Bohr

Answer

Correct option: D.
Bohr
d
Bohr's Model was first to theoretically explain the Line Spectrum of Hydrogen atom and single electron species based on the assumption that electrons can only occupy certain orbits of fixed energy, with energy radiated or absorbed in discrete packets(quanta) during electronic transition, and angular momentum of electron in a orbit is quantized.

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