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Finding Why a Daughter Count Levels Off 4 questions
Finding Why a Daughter Count Levels Off
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A classroom simulation tracks parent nuclei P and their daughter nuclei D. Each P that decays produces one D. Existing D nuclei can also decay into a third type that the display does not count as D. In this step model, each interval removes half of the D present at its start. D nuclei formed during an interval first become eligible to decay in the next interval.
| End of interval | P count | D count |
|---|---|---|
| Start | 80 | 0 |
| 1 | 40 | 40 |
| 2 | 20 | 40 |
| 3 | 10 | Hidden |
Question 1
How many new D nuclei are produced during interval 2?
- 0
- 10
- 20
- 40
Question 2
Explain why the D count stays at 40 at the end of interval 2 even though more D is produced.
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Question 3
Calculate the missing D count at the end of interval 3. Show how you include both sources of change.
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Question 4
A student uses the unchanged D reading after interval 2 to claim that the original parent isotope stopped decaying. Evaluate the claim using both records.
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