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4 years ago

6

One of the many by products of uranium is radioactive plutonium, which has a half life of approximatley 25000 ytears. if some of

this putonium is encased in concrete, what fraction of it will remain after 100 years?

1 answer:

strojnjashka [21]4 years ago

8 0

Answer:

0.9972 fraction of plutonium will remain after 100 years.

Explanation:

Half life of plutonium = $t_{1/2}=25000 years$

Let the initial mass of plutonium be = $A_o$

Mass of plutonium after time of 100 years = A

Decay constant for this process = $\lambda =\frac{0.693}{t_{1/2}}$

$A=A_o\times e^{-\lambda t}$

$A=A_o\times e^{-\frac{0.693}{25000 years}\times 100 year}$

$A=A_o\times 0.9972$

$\frac{A}{A_o}=0.9972$

0.9972 × 100 = 99.72 %

0.9972 fraction of plutonium will remain after 100 years.

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3 years ago

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1)

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where here:

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7)

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8)

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See the last 7 answers in the attached document.

<span class="sg-text sg-text--link sg-text--bold sg-text--link-disabled sg-text--blue-dark"> docx </span>

<span class="sg-text sg-text--link sg-text--bold sg-text--link-disabled sg-text--blue-dark"> pdf </span>

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3 years ago

parallel-plate air capacitor is made from two plates 0.070 m square, spaced 6.3 mm apart. What must the potential difference bet

Rom4ik [11]

Answer:

V = 576 V

Explanation:

Given:

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3 years ago