Nuclear Physics And Radioactivity Question 385
Question: The half-life of a radioactive substance is 40 years. How long will it take to reduce to one fourth of its original amount and what is the value of decay constant [DPMT 2003]
Options:
A) 40 year, 0.9173/year
B) 90 year, 9.017/year
C) 80 year, 0.0173 year
D) None of these
Show Answer
Answer:
Correct Answer: C
Solution:
To reduce one fourth it takes time $ t=2( {T_{1/2}} ) $ = 2 ´ 40 = 80 years. Decay constant $ \lambda =\frac{0.693}{{T_{1/2}}}=\frac{0.693}{40}=0.0173,years $
BETA
