MCQ
An electron initially at rest, is accelerated through a potential difference of $200$ volt, so that it acquires a velocity $8.4 \times 10^6 \mathrm{~m} / \mathrm{s}$. The value of e/m of electron will be
  • A
    $2.76 \times 10^{12} \mathrm{C} / \mathrm{kg}$
  • $1.76 \times 10^{11} \mathrm{C} / \mathrm{kg}$
  • C
    $0.76 \times 10^{12} \mathrm{C} / \mathrm{kg}$
  • D
    None of these

Answer

Correct option: B.
$1.76 \times 10^{11} \mathrm{C} / \mathrm{kg}$
$1.76 \times 10^{11} \mathrm{C} / \mathrm{kg}$

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