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Erdwärme aus Kalium

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Level 5 -
Level 6 -

Exercise

https://texercises.com/exercise/erdwarme-aus-kalium/

Question

Solution

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The following quantities appear in the problem: Masse \(m\) / Energie \(E\) / Aktivität \(A\) / Leistung \(P\) / molare Masse \(M\) / Stoffmenge \(n\) / Zerfallskonstante \(\lambda\) / Anzahl \(N\) /

The following formulas must be used to solve the exercise: \(A = \lambda \cdot N \quad \) \(m = nM \quad \) \(P = A \cdot E_1 \quad \)

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Exercise:
% http://science.orf.at/stories// . Sept. Der Zerfall von Kalium- erzeugt geschätzte PO Erdwärme. Wie viel Masse an isotopeK enthält die Erde demnach? Das Isotop K- hat TO Halbwertszeit und mO Masse; ein Zerfall liefert EeO Energie.

Solution:
Um die angegebene Leistung zu erzeugen müsste pro Sekunde E Pt P s E Energie aus Zerfällen entstehen. Dafür wären N' fracEE_ fracEEe Np Zerfälle pro Sekunde bzw. anders gesprochen eine Aktivität von A fracPE_ fracPEe A notwig. Bei der angegebenen Halbwertszeit müssten dazu N fracAlambda fracAfracln T fracATln fracAlam fracA Tln N Kalium--Isotope vorliegen. Diese haben m N m_ fracPTm_E_ln fracP T mEe ln mt Masse. m fracPTm_E_ln mt

Meta Information

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Contained in these collections:

Aktivität Zerfallsenergie molare Masse by TeXercises

3 | 4
Kern- und Teilchenphysik: Kernphysik by Lie

2 | 10
Zerfallsenergie by uz

9 | 11

Asked Quantity: Masse \(m\) in Kilogramm \(\rm kg\)

Attributes & Decorations

Tags	erdwärme, kalium, nuklearphysik, physik, radioaktivität
Content image
Difficulty	(3, default)
Points	3 (default)
Language	(Deutsch)
Type	Calculative / Quantity
Creator	Lie
Decoration
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