Question

16 gm sample of a radioactive element is taken from Bombay to Delhi in 2 hour and it was found that 1 gm of the element remained (undisintegrated). Half life of the element is

• A. $2hour$
• B. $1hour$
• C. $\frac{1}{2}hour$
• D. $\frac{1}{4}hour$

Answer 1

The correct option is C $\frac{1}{2}hour$

$N=N_0{\left(\frac{1}{2}\right)}^{t/T_{1/2}}\Rightarrow 1=16{\left(\frac{1}{2}\right)}^{2/T_{1/2}}\Rightarrow T_{\frac{1}{2}}=\frac{1}{2}hour$