Question

The half-life of a radioactive nuclide is 100 hours. The fraction of original activity that will remain after 150 hours would be :

(1) 1/2 

(2) 1/2√2

(3) 2/3

(4) 2/3√2

Answer 1

Option : (2) 1/2√2

\(\frac{A}{A_0}\) = \((\frac{1}{2})^{t/T_H}\) 

= \((\frac{1}{2})^{150/100}\) 

= \(\frac{1}{2\sqrt 2}\).