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harkovskaia [24]
3 years ago
7

The half-life of plutonium 239 is 24,200 years. Assume that the decay rate is proportional to the amount. Determine the amount o

f time it would take 3 grams of radium to decay to 2 grams. Round to the nearest hundred.
Physics
1 answer:
kotykmax [81]3 years ago
5 0

Answer:

time taken is equal to 14,156 years

Explanation:

we know,

Y=Ae^{-kt}

at t = 0

Y(0) = A

given that half life of plutonium 239 = 24,200

\dfrac{A}{2}=Ae^{-kt}\\0.5=e^{-kt}\\k\times 24200 = ln(2)\\k = \dfrac{ ln(2)}{24200}

Y=Ae^{-kt}

\frac{3}{2} = e^{-kt}\\ln(1.5)=-\dfrac{ ln(2)}{24200}\times t\\t=-\dfrac{ln(1.5)\times 24200}{ ln(2)}\\t=14,156 \ years

hence time taken is equal to 14,156 years

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