What is the half-life if 1/4 of a sample remains after 20 minutes?
A5 minutes
B10 minutesCORRECT
C15 minutes
D20 minutes
WAECPhysics
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Why the answer is B, and why the others tempt you.
1/4 = (1/2)² → 2 half-lives in 20 min → each half-life = 10 min.
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