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Atomic and Nuclear Physics — Physics STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsAtomic and Nuclear Physics1 Mark
MCQ
Two radioactive materials $X_1$ and $X_2$ have decay constants $10\lambda$ and $\lambda$ respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of $X_1$ to that of $X_2$  will be $1/e$  after a time
  • A
    $1/(10 \lambda )$
  • B
    $1/(11 \lambda )$
  • C
    $11(10 \lambda )$
  • ✓
    $1(9 \lambda )$
✓

Answer

Correct option: D.
$1(9 \lambda )$
$1(9 \lambda )$

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