MCQ
Which one is correct relation for thermionic emission
  • A
    $\ce{J=A T^{1 / 2} e^{-\emptyset / k T}}$
  • $\mathrm{J}=\mathrm{AT}^2 \mathrm{e}^{-\emptyset / \mathrm{kT}}$
  • C
    $\mathrm{J}=\mathrm{AT}^{3 / 2} \mathrm{e}^{-\emptyset / \mathrm{kT}}$
  • D
    $\ce{J=A T^2 e^{-\emptyset / 2 k T}}$

Answer

Correct option: B.
$\mathrm{J}=\mathrm{AT}^2 \mathrm{e}^{-\emptyset / \mathrm{kT}}$
$\mathrm{J}=\mathrm{AT}^2 \mathrm{e}^{-\emptyset / \mathrm{kT}}$

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