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Autofokus von Fotokamera

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.

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 -

Exercise

https://texercises.com/exercise/autofokus-von-fotokamera/

Question

Solution

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Exercise:
Eine Fotokamera stellt das Bild eines Rennautos dauernd scharf. Das Auto fährt mit Geschwindigkeit v auf die Kamera zu oder von ihr weg. Das Objektiv sei vereinfacht eine Linse mit Brennweite f. Mit welcher Geschwindigkeit wird die Linse bewegt?

Solution:
% Lie. . April Sei g die Gegenstandsweite b die Bildweite und sg+b der Abstand BildebenRennauto. Die Bildebene bewegt sich nicht. Dann ist v fracddsddt die Geschwindigkeit des Rennautos und fracddbddt die Geschwindigkeit der Linse ohne Betrachtung der Richtung. * fracf fracg + fracb fracf fracs-b + fracb bs - b^ fb + fs-fb b^ -bs+fs b_ fracs pm sqrts^ -fs * * fracddbddt frac fracddsddt pm frac fracsqrts^ -fs left sfracddsddt-ffracddsddt right fracddbddt frac v pm frac fracsv-fvsqrts^ -fs fracddbddt fracv left pm fracs-fsqrts^ -fs right * Die Geschwindigkeit mit der die Linse bewegt respektive die Bildweite vergrössert werden muss hängt wie erwartet von der Geschwindigkeit des Rennautos proportional sowie vom momentanen Abstand des Autos und von der Brennweite der Linse ab.

Meta Information

\(\LaTeX\)-Code

Contained in these collections:

Infinitesimalrechnung: Differentialrechnung by Lie

1 | 5
DGL in der Physik 1 by uz

3 | 8

Attributes & Decorations

Tags	Rennauto_scharfstellen
Content image
Difficulty	(4, default)
Points	4 (default)
Language	(Deutsch)
Type	Calculative / Quantity
Creator	Lie
Decoration
File
Link