MCQ
The De-broglie $\lambda$ of electron in the $2^{st}$ Bohr orbit is
  • A
     $4\pi r_1$
  • $\pi r_1$
  • C
    $2\pi r_1$
  • D
    $6\pi r_1$

Answer

Correct option: B.
$\pi r_1$
b

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