Recent content by abcd112358

In (a part of) germany there was a change in the curriculum about 15 years ago. With this change there was an introduction to a (simple) numerical method where studets of 10th grade use Excel to analyze position, speed and velocity of a pendulum or a falling object including air resistance...

Maybe it is because of my lackluster translation. Alternative translations (instead of "decriptive") might be "graphic", "demonstrative" or maybe "vivid", although I think "graphic" would be the next best translation. And yes. All the parts of these circuits are usually treated as ideal. Later...

Maybe I communicated the situation not clearly. Sorry about that. These lessons are nice and I already did them in different grades fitting to the curriculum, but they won't give the students a mental image of what is going on inside the wire that is analoguos to reality. Two other problems: 1...

About 14 years old (+/- 1 year) Later on there will be calculations involved (R=UI and calculation of the combined resistance of series connections and of shunt connections). They are able to solve simple linear equations and simple equations involving variables in fractions as long as they can...

This is a great point. I like it a lot. In the marble model voltage would be represented by the force that pushes the marbles through the tube und current would be pretty much be simply represented by the number of marbles passing through at a time? The model does not need to give any insight...

What would be the advantages of the marble model compared to a watermodel with closed waterpipes? I don't think the nonlinearity of the resistance is a problem for the exercises noted above. I can see how you could explain observations in a series connection (all marbles still move at the same...

Since this quesstion popped up in this thread I thought it might be better to create a new thread: https://www.physicsforums.com/threads/a-question-about-an-electrons-movement-in-a-dc-circuit.997736/ The question is the following: What kind of descriptive model could/should one use while first...

What modle would you prefere techers to show young students, when first trying to make the abstract thing that is electricity a bit more available? I know that some people have huge problems getting rid of wrong concepts later on, but when students learn about electricity in say 7th grade not...

I see two mistakes right now. 1. You left out the factor of 2 you derived in your step number 5 2. You forgot to set one bracket: Your step from $$x^{2^{log_x(2)}}$$ to $$x\cdot x^{log_x(2)}$$ is wrong. There need to be brackets around both x: $$(x\cdot x)^{log_x(2)}$$ Therefore the exponent...