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Iglu

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/iglu-4/

Question

Solution

Short

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The following quantities appear in the problem: Zeit \(t\) / Temperatur \(T\) / Arbeit \(W\) / Energie \(E\) / Leistung \(P\) / Fläche \(A\) / Radius \(r\) / Oberfläche \(S\) / Dicke \(d\) /

The following formulas must be used to solve the exercise: \(S = 4 \pi r^2 \quad \) \(P = \dfrac{E}{t} = \dfrac{W}{t} \quad \) \(\Phi = \lambda \dfrac{T_1-T_2}{d}A \quad \)

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Exercise:
Ein Iglu dessen Form vereinfacht als Halbkugel betrachtet werden kann werde aus festgestampftem Schnee mit einer Wärmeleitfähigkeit von .wattperkelvinpermeter errichtet. Die Dicke der Wände des Iglus betrage cm. Die Bewohner des Iglus geben pro Tag eine Wärme von etwa MJ ab und können damit selbst bei einer Aussentemperatur von -degreeCelsius im Innern eine Temperatur von degreeCelsius aufrecht erhalten. Berechne den Radius der Igluhalbkugel.

Solution:
boxGegeben lambda .wattperkelvinpermeter d cm .m t ds Q MJ .eJ theta_ -degreeCelsius theta_ degreeCelsius boxGesucht textRadius rsim Die Wärmeleistung der Iglubewohner beträgt: Phi fracQt .eW Bei einer Temperaturdifferenz von Delta T theta_-theta_ K darf die Igluwandfläche aus Schnne höchstens A fracPhi dlambda Delta T fracfracQt dlambda theta_-theta_ fracQ dlambda t theta_-theta_ frac.eW .m.wattperkelvinpermeter K .emetersquared betragen. Der Radius der Halbkugel ist somit: r sqrtfracApi sqrtfracQ dpi lambda t theta_-theta_ sqrtfrac.emetersquaredpi .m boxbox r sqrtfracQ dpi lambda t theta_-theta_ .m

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Attributes & Decorations

Branches	Heat Transfer
Tags	fläche, iglu, kugel, physik, schnee, thermodynamik, wärmelehre, wärmeleitfähigkeit, wärmeleitung, wärmestrom
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Difficulty	(3, default)
Points	5 (default)
Language	(Deutsch)
Type	Calculative / Quantity
Creator	uz
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