- Home
- Standard 12
- Physics
13.Nuclei
medium
Starting with a sample of pure $^{66}Cu,\,\frac{7}{8}$ of it decays into $Zn$ in $15\, min$. The corresponding half-life is .......... $min$
A
$5$
B
$7\frac{1}{2}$
C
$10$
D
$15$
(AIEEE-2005)
Solution
(a) $\frac{7}{8}$part decays $i.e.$ remaining part is $\frac{1}{8}$
$N = {N_0}{\left( {\frac{1}{2}} \right)^{\frac{t}{{{T_{1/2}}}}}}$
$ \Rightarrow \frac{1}{8} = {\left( {\frac{1}{2}} \right)^{\frac{{15}}{{{T_{1/2}}}}}} \Rightarrow {T_{1/2}} =5\, min.$
Standard 12
Physics
