A) 6000
B) 9000
C) 3000
D) 24000
Correct Answer: D
Solution :
Here the activity of the radioactive sample reduces to half in 140 days. Therefore, the half life of the sample is 140 days. 280 days is it?s two half lives. So before two half lives it?s activity was \[({{2}^{2}}\times \] present activity). \ Initial activity = \[{{2}^{2}}\times 6000=24000\,dps.\]
You need to login to perform this action.
You will be redirected in
3 sec
