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Wieder eine Leiter an der Wand

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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/wieder-eine-leiter-an-der-wand/

Question

Solution

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Need help? Yes, please!

The following quantities appear in the problem: Drehmoment \(\vec M\) /

The following formulas must be used to solve the exercise: \(\sum \stackrel{\curvearrowleft}{M} \stackrel{!}{=} \sum \stackrel{\curvearrowright}{M} \quad \)

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No explanation / solution video for this exercise has yet been created.
But there is a video to a similar exercise:

In case your browser prevents YouTube embedding: https://youtu.be/FZAILXUJlnI

Exercise:
Eine homogene Leiter der Länge l mit der Masse m_Lkg lehne an einer Wand. Die Haftreibungszahl betrage mu_ . zwischen Leiter und Wand bzw. mu_. zwischen Leiter und Boden. Ein Feuerwehrmann mit m_F kg Masse habe / der Leiterhöhe erreicht als die Leiter zu rutschen nt. Bestimmen Sie den Winkel theta zwischen Leiter und Boden. Der Feuerwehrmann ist als Massenpunkt zu betrachten.

Solution:
Wählen wir als Drehpunkt den Kontaktpunkt der Leiter mit dem Boden. Dann ist die Drehmomentgleichung: m_Lgfraclcostheta + m_Fgfraclcostheta - F_Nlsheta-F_Rlcostheta Um diese Gleichung lösen zu können müssen wir F_N und F_R kennen. Diese können über das Kräftegleichgewicht bestimmt werden: F_R - F_N und F_N+F_R m_F+m_Lg. Daraus folgt: F_N fracmu_m_F+m_Lg+mu_mu_. Nun können wir die erste Gleichung nach theta auflösen tantheta fracfracm_Lg+fracm_Fg-mu_F_NF_N Rightarrow theta approx .grad.

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Tags	drehmoment, mechanik, statik
Content image
Difficulty	(3, default)
Points	0 (default)
Language	(Deutsch)
Type	Calculative / Quantity
Creator	cm
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