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stealth61 [152]
3 years ago
5

Francium-223 has a half-life of 22 minutes. A Geiger counter gives a reading of 58 counts per minute (cpm) from a sample of fran

cium-223. What will the reading be 22 minutes later? You can ignore background radiation.
Physics
1 answer:
polet [3.4K]3 years ago
8 0

Answer:

29 counts per minute (29 cpm)

Explanation:

The half-life of a radioactive isotope is the time needed for the activity of the sample to halve.The half-life of Francium-223 is exactly 22 minutes: this means that its activity after 22 minutes becomes exactly half of its initial value. Since the initial activity of this sample of francium-223 was 58 cpm, the activity after 22 minutes will be

A=\frac{58 cpm}{2}=29 cpm

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The question is incomplete. The complete question is :

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The normal force represented by N is equal to the downward force, $F_d$ which is equal in magnitude but it is opposite in direction.

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Which factors affect the gravitational force between objects? Check all that apply.
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Explanation:

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Answer:

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Explanation:

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The sample appears to have gone through 3 half-lives
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