Chemical Engineering - Nuclear Power Engineering - Discussion
Discussion Forum : Nuclear Power Engineering - Section 2 (Q.No. 27)
27.
75% of a radioactive element decays in 6 hours. Its half life period is __________ hours.
Discussion:
2 comments Page 1 of 1.
Colossus said:
8 years ago
I think the answer is 4. If 75% decay in 6hrs. 1% will decay in 6/75 hours and 50% will decay in 50*6/75 hrs= 4hrs.
Abir said:
8 years ago
0.25a=ae^6k,
ln0.25=6k
k=-0.23,
again, 0.5a=ae^-0.23t,
ln0.5=-0.23t,
t=3.
ln0.25=6k
k=-0.23,
again, 0.5a=ae^-0.23t,
ln0.5=-0.23t,
t=3.
(1)
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