How long must you wait (in half-lives) for a radioactive sample to drop to 5.00 %...

Question

Question

How long must you wait (in half-lives) for a radioactive sample to drop to 5.00 % of its original activity?

science physics

Answer 1

Answer #1

Let n be the number of half lives,

(1/2)^n = 0.05

So, n = ln(0.05)/ln(0.5)

= 4.32 half lives

Answer 2

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