The half-life of a radioactive nuclide is 100 hours. The fraction of original activity that will remain after 150 hours would be :
Correct Answer :
1/(2√2)
Solution :
The correct option is 1/(2√2).
To find the fraction of the original radioactive activity that remains after a certain amount of time, we can use the radioactive decay formula based on the number of half-lives. The formula is:
Where:
- is the final amount of activity remaining.
- is the initial amount of activity.
- is the number of half-lives that have elapsed.
First, we calculate the number of half-lives () by dividing the total time elapsed () by the half-life ():
Now, substitute into the decay formula to find the fraction remaining:
We can simplify this exponential expression step-by-step:
A fractional exponent of 3/2 is equivalent to cubing the number and taking the square root:
Since , we have:
Finally, we can simplify the radical by factoring out a perfect square (), taking the square root of 4 out of the radical:
Thus, the fraction of the original activity that will remain is .
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