更新1:
1) 12 hours 2) 24 hours 3) 36 hours 4) 8 hours 5) 72 hours
In 72 hours the amount of a radioactive substance has reduced from 40 mg to 20 mg. What is the half-life of this isotope?
回答 (5)
2016-07-13 8:51 am
Fraction of the isotope remained = (20 mg) / (40 mg) = 1/2
Hence, time taken = 1 half-life = 72 hours
Half-life of this isotope = 72 hours
...... The answer is : 5) 72 hours
Hence, time taken = 1 half-life = 72 hours
Half-life of this isotope = 72 hours
...... The answer is : 5) 72 hours
2016-07-13 4:08 am
What is a half life? That will give you the answer.
2016-07-13 6:34 am
72 hours is the half life.
2016-07-13 4:50 am
72 hours.
2016-07-13 4:33 am
5?
收錄日期: 2021-04-18 15:16:59
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