Fossil of ancient animal
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
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Exercise:
The rubidium isotope isotopeRb is a beta^- emitter with halflife pq.ea. A certain rock contains a fossil of an ancient animal; scientists determine in this rock a ratio of isotopeSr to isotopeRb of numpr.. Asing there was no isotopeSr present when the rock was formed estimate the age of the fossil.
Solution:
If there was no Strontium present in the ``ning" all Strontium origins from beta^--decays of Rubidium. The number of Strontium isotopes we observe later is then tilde N N_ - N_t where N_ denotes the number of Rubidium isotopes in the ning and N_t the number at a later time t. Since N_t N_ e^-lambda t quad textand N_ N_t e^+lambda t for any radioactive decaying isotope we can for the amount of Strontium write tilde N N_t e^+lambda t - N_t lefte^+lambda t-right N_t. The radio of Strontium to Rubidium is given therefor we can solve the last for the age of the fossil: t fraclambda left+fractilde NN_tright fracT_hln left+fractilde NN_tright pq.ea.
The rubidium isotope isotopeRb is a beta^- emitter with halflife pq.ea. A certain rock contains a fossil of an ancient animal; scientists determine in this rock a ratio of isotopeSr to isotopeRb of numpr.. Asing there was no isotopeSr present when the rock was formed estimate the age of the fossil.
Solution:
If there was no Strontium present in the ``ning" all Strontium origins from beta^--decays of Rubidium. The number of Strontium isotopes we observe later is then tilde N N_ - N_t where N_ denotes the number of Rubidium isotopes in the ning and N_t the number at a later time t. Since N_t N_ e^-lambda t quad textand N_ N_t e^+lambda t for any radioactive decaying isotope we can for the amount of Strontium write tilde N N_t e^+lambda t - N_t lefte^+lambda t-right N_t. The radio of Strontium to Rubidium is given therefor we can solve the last for the age of the fossil: t fraclambda left+fractilde NN_tright fracT_hln left+fractilde NN_tright pq.ea.
Meta Information
Exercise:
The rubidium isotope isotopeRb is a beta^- emitter with halflife pq.ea. A certain rock contains a fossil of an ancient animal; scientists determine in this rock a ratio of isotopeSr to isotopeRb of numpr.. Asing there was no isotopeSr present when the rock was formed estimate the age of the fossil.
Solution:
If there was no Strontium present in the ``ning" all Strontium origins from beta^--decays of Rubidium. The number of Strontium isotopes we observe later is then tilde N N_ - N_t where N_ denotes the number of Rubidium isotopes in the ning and N_t the number at a later time t. Since N_t N_ e^-lambda t quad textand N_ N_t e^+lambda t for any radioactive decaying isotope we can for the amount of Strontium write tilde N N_t e^+lambda t - N_t lefte^+lambda t-right N_t. The radio of Strontium to Rubidium is given therefor we can solve the last for the age of the fossil: t fraclambda left+fractilde NN_tright fracT_hln left+fractilde NN_tright pq.ea.
The rubidium isotope isotopeRb is a beta^- emitter with halflife pq.ea. A certain rock contains a fossil of an ancient animal; scientists determine in this rock a ratio of isotopeSr to isotopeRb of numpr.. Asing there was no isotopeSr present when the rock was formed estimate the age of the fossil.
Solution:
If there was no Strontium present in the ``ning" all Strontium origins from beta^--decays of Rubidium. The number of Strontium isotopes we observe later is then tilde N N_ - N_t where N_ denotes the number of Rubidium isotopes in the ning and N_t the number at a later time t. Since N_t N_ e^-lambda t quad textand N_ N_t e^+lambda t for any radioactive decaying isotope we can for the amount of Strontium write tilde N N_t e^+lambda t - N_t lefte^+lambda t-right N_t. The radio of Strontium to Rubidium is given therefor we can solve the last for the age of the fossil: t fraclambda left+fractilde NN_tright fracT_hln left+fractilde NN_tright pq.ea.
Contained in these collections
| Title | Creator | Matched on |
|---|---|---|
| Beryllium on leaf of a plant | uz | tags |
| Decay Chain | by | tags |
| Three-Stage Decay Chain | by | tags |

