Nuclear Physics And Radioactivity Question 347

Question: Three fourth of the active decays in a radioactive sample in 3/4 sec. The half life of the sample is [KCET (Engg.) 2001]

Options:

A) $ \frac{1}{2} $ sec

B) 1 sec

C) $ \frac{3}{8} $ sec

D) $ \frac{3}{4} $ sec

Show Answer

Answer:

Correct Answer: C

Solution:

$ \frac{3}{4}th $ active decay takes place in time $ t=2,({T_{1/2}}) $

Þ $ \frac{3}{4}=2,({T_{1/2}}) $

Þ $ {T_{1/2}}=\frac{3}{8}\sec $