Nuclear Physics And Radioactivity Question 346
Question: In a mean life of a radioactive sample [MP PMT 2000, 03]
Options:
A) About 1/3 of substance disintegrates
B) About 2/3 of the substance disintegrates
C) About 90% of the substance disintegrates
D) Almost all the substance disintegrates
Show Answer
Answer:
Correct Answer: B
Solution:
By using $ N=N_{0}{{e}^{-\lambda t}} $ and $ t=\tau =\frac{1}{\lambda } $ Substance remains $ =N=\frac{N_{0}}{e}=0.37N_{0}\tilde{},\frac{N_{0}}{3} $ \ Substance disintegrated $ =N_{0}-\frac{N_{0}}{3}=\frac{2N_{0}}{3} $
BETA
