An isotope has an initial activity of 120 Bq. 6 days later its activity is 15 Bq. The half-life is?
3 days
2 days
1 day
4 days
Explanation
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Discussions (12)
Why am the first to comment because this is wrong
Answer is 2 days
Myschool didn't finish the calculations
The 3 they got means how many of the half life
x × 3 = 6
X= 2
Assuming the answer is 3 days
I. e the half life is 3days
After the first 3 days= 1/2 ×120= 60
After another 3 days = 1/4 ×16+20 = 30
6 days is complete
Remember question said after 6 days
Assuming answer = 2 days
I.e = half life = 2 days
After the first 2days = 1/2 ×120 =60
After the second 2 days =1/4 ×120 =30
After the third 2 days = 1/8× 120 = 15
6 days is complete
Remember the question after 6 days
6 days is complete and it is remaining 15
I.e the half-life is 2 days
