A) 100 s
B) 20 s
C) 10 s
D) 50 s
Correct Answer: B
Solution :
[b] \[A={{A}_{0}}{{e}^{-\gamma t}}\] |
\[A=\frac{{{A}_{0}}}{2}\]after 10 oscillations |
\[\because \]After 2 seconds |
\[\frac{{{A}_{0}}}{2}={{A}_{0}}{{e}^{-\gamma }}^{(2)}\] |
\[2={{e}^{2\gamma }}\] |
\[\ell n2=2\gamma \] |
\[\gamma =\frac{\ell n2}{2}\] |
\[\because \]\[A={{A}_{0}}{{e}^{-\gamma t}}\] |
\[\ell n\frac{{{A}_{0}}}{A}=\gamma t\] |
\[\ell n1000=\frac{\ell n2}{2}t\] |
\[2\left( \frac{3\ell n10}{\ell n2} \right)=t\] |
\[\frac{6\ell n10}{\ell n2}=t\] |
\[t=19.931\sec \] |
\[t\approx 20\sec \] |
You need to login to perform this action.
You will be redirected in
3 sec