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Radioactivity taken up by cells

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Exercise

https://texercises.com/exercise/radioactivity-taken-up-by-cells-1/

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Solution

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The following quantities appear in the problem: Zeit \(t\) / Zerfallskonstante \(\lambda\) / Anzahl \(N\) / Verhältnis / Anteil \(\eta\) /

The following formulas must be used to solve the exercise: \(\eta = \dfrac{a}{A} \quad \) \(N_t = N_0 \cdot \text{e}^{-\lambda t} \quad \)

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Exercise:
In a certain experiment isotopeP half life .d is injected o a medium containing a culture of bacteria. After min the cells are washed and a detector that is % efficient i.e. counts % percent of emitted upbeta rays records counts per minute from all the cells. Calculate the activity of the original Phosphor-source under the asption that the cells took up .% of the Phosphor.

Solution:
boxGegeben T .d .es t min s eta' % . A_d per-modereciprocalperminute .Bq eta .% . boxGesucht textInitial activity A_siBq After min the Phosphor's acitivty within the cells -- since the detector registers only % -- is: A_c fracA_deta' frac.Bq. Bq And because the cells took only .% of the Phosphor up the overall Phosphor's activity including the Phosphor that wasn't taken up by the cells must be: A_t fracA_ceta fracA_deta' eta fracBq. .Bq This activity was min earlier: A_ A_t mathrme^+fracln Tt A_t ^+fractT fracA_deta' eta mathrme^+fracln Tt Bq boxbox A_ fracA_deta' eta mathrme^+fracln Tt Bq

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Radioactivity taken up by cells by TeXercises

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Attributes & Decorations

Tags	biology, cells, phosphor, physics, radioactivity, radiometry
Content image
Difficulty	(3, default)
Points	3 (default)
Language	(Deutsch)
Type	Calculative / Quantity
Creator	uz
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