MCQ
When a hydrogen atom is raised from the ground state to an excited state
  • $P.E.$ increases and $K.E.$ decreases
  • B
    $P.E.$ decreases and $K.E.$ increases
  • C
    Both kinetic energy and potential energy increase
  • D
    Both $K.E.$ and $P.E.$ decrease

Answer

Correct option: A.
$P.E.$ increases and $K.E.$ decreases
a
(a) $P.E.$ $ \propto - \frac{1}{r}$ and $K.E.$ $ \propto \frac{1}{r}$
As $r$ increases so $K.E.$ decreases but $P.E.$ increases.

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