A) \[8.6\times {{10}^{6}}s\]
B) \[4.2\times {{10}^{5}}s\]
C) \[3.1\times {{10}^{5}}s\]
D) \[1.1\times {{10}^{6}}s\]
Correct Answer: A
Solution :
[a] The total number of protons bombarded \[=\frac{it}{\lambda }=\frac{{{10}^{-4}}\times 3600}{1.6\times {{10}^{-19}}}=22.5\times {{10}^{17}}\] Number of \[^{7}Be\] produced \[N=\frac{22.5\times {{10}^{17}}}{1000}=22.5\times {{10}^{14}}\] We know that activity \[A=\lambda \,\,N\] or \[A=\left( \frac{0.693}{{{t}_{1/2}}} \right)N\] \[\therefore \,\,\,\,\,\,\,\,\,{{t}_{1/2}}=0.693\frac{N}{A}=0.693\times \frac{22.5\times {{10}^{14}}}{1.8\times {{10}^{8}}}\] \[=8.63\times {{10}^{6}}s\]
You need to login to perform this action.
You will be redirected in
3 sec
