Nuclear Physics And Radioactivity Question 364
Question: In a sample of radioactive material, what percentage of the initial number of active nuclei will decay during one mean life [KCET 2002]
Options:
A) 69.3%
B) 63%
C) 50%
D) 37%
Show Answer
Answer:
Correct Answer: B
Solution:
Number of atoms remains undecayed $ N=N_{0}{{e}^{-\lambda t}} $ Number of atoms decayed = $ N_{0}(1-{{e}^{-\lambda t}}) $ $ =,N_{0},( 1-{{e}^{-\lambda \times \frac{1}{\lambda }}} )=N_{0}( 1-\frac{1}{e} ) $ $ =0.63,N_{0}=63% $ of N0 .
BETA
