Nuclear Physics And Radioactivity Question 279
Question: A radio-isotope has a half- life of 5 years. The fraction of the atoms of this material that would decay in 15 years will be [NCERT 1984; MP PMT 1996; MP PET 1997]
Options:
A) 1/8
B) 2/3
C) 7/8
D) 5/8
Show Answer
Answer:
Correct Answer: C
Solution:
$ \frac{N}{N_{0}}={{( \frac{1}{2} )}^{15/5}}=\frac{1}{8} $
Þ Decayed fraction $ =1-\frac{1}{8}=\frac{7}{8} $
BETA
