Fossilienalter mit Rubidium-Strontium-Methode
About points...
We associate a certain number of points with each exercise.
When you click an exercise into a collection, this number will be taken as points for the exercise, kind of "by default".
But once the exercise is on the collection, you can edit the number of points for the exercise in the collection independently, without any effect on "points by default" as represented by the number here.
That being said... How many "default points" should you associate with an exercise upon creation?
As with difficulty, there is no straight forward and generally accepted way.
But as a guideline, we tend to give as many points by default as there are mathematical steps to do in the exercise.
Again, very vague... But the number should kind of represent the "work" required.
When you click an exercise into a collection, this number will be taken as points for the exercise, kind of "by default".
But once the exercise is on the collection, you can edit the number of points for the exercise in the collection independently, without any effect on "points by default" as represented by the number here.
That being said... How many "default points" should you associate with an exercise upon creation?
As with difficulty, there is no straight forward and generally accepted way.
But as a guideline, we tend to give as many points by default as there are mathematical steps to do in the exercise.
Again, very vague... But the number should kind of represent the "work" required.
About difficulty...
We associate a certain difficulty with each exercise.
When you click an exercise into a collection, this number will be taken as difficulty for the exercise, kind of "by default".
But once the exercise is on the collection, you can edit its difficulty in the collection independently, without any effect on the "difficulty by default" here.
Why we use chess pieces? Well... we like chess, we like playing around with \(\LaTeX\)-fonts, we wanted symbols that need less space than six stars in a table-column... But in your layouts, you are of course free to indicate the difficulty of the exercise the way you want.
That being said... How "difficult" is an exercise? It depends on many factors, like what was being taught etc.
In physics exercises, we try to follow this pattern:
Level 1 - One formula (one you would find in a reference book) is enough to solve the exercise. Example exercise
Level 2 - Two formulas are needed, it's possible to compute an "in-between" solution, i.e. no algebraic equation needed. Example exercise
Level 3 - "Chain-computations" like on level 2, but 3+ calculations. Still, no equations, i.e. you are not forced to solve it in an algebraic manner. Example exercise
Level 4 - Exercise needs to be solved by algebraic equations, not possible to calculate numerical "in-between" results. Example exercise
Level 5 -
Level 6 -
When you click an exercise into a collection, this number will be taken as difficulty for the exercise, kind of "by default".
But once the exercise is on the collection, you can edit its difficulty in the collection independently, without any effect on the "difficulty by default" here.
Why we use chess pieces? Well... we like chess, we like playing around with \(\LaTeX\)-fonts, we wanted symbols that need less space than six stars in a table-column... But in your layouts, you are of course free to indicate the difficulty of the exercise the way you want.
That being said... How "difficult" is an exercise? It depends on many factors, like what was being taught etc.
In physics exercises, we try to follow this pattern:
Level 1 - One formula (one you would find in a reference book) is enough to solve the exercise. Example exercise
Level 2 - Two formulas are needed, it's possible to compute an "in-between" solution, i.e. no algebraic equation needed. Example exercise
Level 3 - "Chain-computations" like on level 2, but 3+ calculations. Still, no equations, i.e. you are not forced to solve it in an algebraic manner. Example exercise
Level 4 - Exercise needs to be solved by algebraic equations, not possible to calculate numerical "in-between" results. Example exercise
Level 5 -
Level 6 -
Question
Solution
Short
Video
\(\LaTeX\)
Need help? Yes, please!
The following quantities appear in the problem:
Zeit \(t\) / Halbwertszeit \(T\) / Anzahl \(N\) /
The following formulas must be used to solve the exercise:
\(t = \frac{T}{\ln 2} \cdot \ln\left(\frac{N_2}{N_1}+1\right) \quad \)
No explanation / solution video to this exercise has yet been created.
Visit our YouTube-Channel to see solutions to other exercises.
Don't forget to subscribe to our channel, like the videos and leave comments!
Visit our YouTube-Channel to see solutions to other exercises.
Don't forget to subscribe to our channel, like the videos and leave comments!
Exercise:
Das Rubidiumisotop isotopeRb ist ein upbeta-Strahler welcher Formelbuchmit einer Halbwertszeit von TO in isotopeSr zerfällt. Das Isotop wird zur Bestimmung des Alters von Steinen und Fossilien genutzt. Berechne das Alter von Steinen welche Fossilien früherer Tiere enthalten und ein Verhältnis von isotopeSr zu isotopeRb von ntO ausweisen. Nimm dabei an dass ursprünglich kein isotopeSr vorhanden war.
Solution:
Falls anfänglich kein Strontium vorgelegen hat so kommt alles Strontium vom Zerfall des Rubidiums; die Anzahl Strontium-Isotope nach einer gewissen Zeit ist also N_t' N_ - N_t N_t ^+fractT -N_t N_t left^+fractT-right was dem Unterschied der Anzahl Rubidium-Isotope am Anfang und Ende entspricht. Für das Verhältnis von Strontium zu Rubidium gilt also eta_t fracN'_tN_t fracN_t left^+fractT-rightN_t ^+fractT-. Somit ist das Fossil t T lblefteta_t +right T fraclneta_t +ln T lbleftnt +right t ta alt. t T lblefteta_t +right T fraclneta_t +ln t ta
Das Rubidiumisotop isotopeRb ist ein upbeta-Strahler welcher Formelbuchmit einer Halbwertszeit von TO in isotopeSr zerfällt. Das Isotop wird zur Bestimmung des Alters von Steinen und Fossilien genutzt. Berechne das Alter von Steinen welche Fossilien früherer Tiere enthalten und ein Verhältnis von isotopeSr zu isotopeRb von ntO ausweisen. Nimm dabei an dass ursprünglich kein isotopeSr vorhanden war.
Solution:
Falls anfänglich kein Strontium vorgelegen hat so kommt alles Strontium vom Zerfall des Rubidiums; die Anzahl Strontium-Isotope nach einer gewissen Zeit ist also N_t' N_ - N_t N_t ^+fractT -N_t N_t left^+fractT-right was dem Unterschied der Anzahl Rubidium-Isotope am Anfang und Ende entspricht. Für das Verhältnis von Strontium zu Rubidium gilt also eta_t fracN'_tN_t fracN_t left^+fractT-rightN_t ^+fractT-. Somit ist das Fossil t T lblefteta_t +right T fraclneta_t +ln T lbleftnt +right t ta alt. t T lblefteta_t +right T fraclneta_t +ln t ta
Meta Information
Exercise:
Das Rubidiumisotop isotopeRb ist ein upbeta-Strahler welcher Formelbuchmit einer Halbwertszeit von TO in isotopeSr zerfällt. Das Isotop wird zur Bestimmung des Alters von Steinen und Fossilien genutzt. Berechne das Alter von Steinen welche Fossilien früherer Tiere enthalten und ein Verhältnis von isotopeSr zu isotopeRb von ntO ausweisen. Nimm dabei an dass ursprünglich kein isotopeSr vorhanden war.
Solution:
Falls anfänglich kein Strontium vorgelegen hat so kommt alles Strontium vom Zerfall des Rubidiums; die Anzahl Strontium-Isotope nach einer gewissen Zeit ist also N_t' N_ - N_t N_t ^+fractT -N_t N_t left^+fractT-right was dem Unterschied der Anzahl Rubidium-Isotope am Anfang und Ende entspricht. Für das Verhältnis von Strontium zu Rubidium gilt also eta_t fracN'_tN_t fracN_t left^+fractT-rightN_t ^+fractT-. Somit ist das Fossil t T lblefteta_t +right T fraclneta_t +ln T lbleftnt +right t ta alt. t T lblefteta_t +right T fraclneta_t +ln t ta
Das Rubidiumisotop isotopeRb ist ein upbeta-Strahler welcher Formelbuchmit einer Halbwertszeit von TO in isotopeSr zerfällt. Das Isotop wird zur Bestimmung des Alters von Steinen und Fossilien genutzt. Berechne das Alter von Steinen welche Fossilien früherer Tiere enthalten und ein Verhältnis von isotopeSr zu isotopeRb von ntO ausweisen. Nimm dabei an dass ursprünglich kein isotopeSr vorhanden war.
Solution:
Falls anfänglich kein Strontium vorgelegen hat so kommt alles Strontium vom Zerfall des Rubidiums; die Anzahl Strontium-Isotope nach einer gewissen Zeit ist also N_t' N_ - N_t N_t ^+fractT -N_t N_t left^+fractT-right was dem Unterschied der Anzahl Rubidium-Isotope am Anfang und Ende entspricht. Für das Verhältnis von Strontium zu Rubidium gilt also eta_t fracN'_tN_t fracN_t left^+fractT-rightN_t ^+fractT-. Somit ist das Fossil t T lblefteta_t +right T fraclneta_t +ln T lbleftnt +right t ta alt. t T lblefteta_t +right T fraclneta_t +ln t ta
Contained in these collections:
-
Altersbestimmung mit Verhältnis zweier Isotope by TeXercises
-
Radiometrische Datierung by pw
-
Radiometrische Datierung by aej
Asked Quantity:
Zeit \(t\)
in
Sekunde \(\rm s\)
Physical Quantity
Die Zeit beschreibt die Abfolge von Ereignissen, hat also eine eindeutige, nicht umkehrbare Richtung.
Unit
Seit 1967 ist eine Sekunde das 9.192.631.770-fache der Periodendauer der Strahlung, die dem Übergang zwischen den beiden Hyperfeinstrukturniveaus des Grundzustandes von Atomen des Nuklids 133Cs entspricht.
Base?
SI?
Metric?
Coherent?
Imperial?

