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4 years ago

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The half-life of a certain substance is 26 years. How long will it take for a sample of this substance to decay to 92% of its

original amount? Use the exponential decay model, A = A_0 e kt, to solve. years (Round to one decimal place as needed.)

1 answer:

Nana76 [90]4 years ago

3 0

Answer:

t= 3.1 years

Step-by-step explanation:

A = A_0 e kt

Half life(1/2) = 26 yrs

1/2 = 1_0 e^k.26

ln(1/2) = ln(e^26k)

26k. ln(e) = ln(1/2)

k = 1/26* ln(1/2)

k = -0.0267

A = A_0 e^kt

0.92 = 1.e^(-0.0267)t

ln(0.92) = ln(e^(-0.0267)t

-0.0267t .ln(e) = ln(0.92)

t = ln(0.92) / -0.0267

t = 3.122

t = 3.1years (approximate to 1 d.p)

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