Magnetic Forces and Induction Setups

The setup below is pretty nice for induction across coils, done by either flipping a switch or varying the power supply manually. Here’s a short video. You can also grab the slinky coils and change the coil density to induce current. Here’s a quick look, and another.

This setup below is good for exploring how changes to magnetic flux can induce current. You can squeeze the loop, rotate the loop, or move it into and out the field. Here is a short video showing how it works.

This rails and rod setup can be used for either induction or a rail gun. It’s similar in look and feel to many textbook rail gun problems. Here is a short video I put up.

Below is the “classic” University of Washington Tutorials magnetic force on a wire set up.

Tiered (1D Forces) Problems

This semester I tinkered with writing problems that assess the same content but at different levels of sophistication.

I found this kind of thing useful in getting a better sense of students’ strengths and weaknesses, and hope to explore it more in the future.

Who taught me this racing game?

I’m guessing it was Frank who taught me this game, but from what I remember the rules are something like

  1. Your velocity vector updates your position.
  2. Each turn, you must accelerate your velocity vector by 1 square —  up, down, left, or right.
  3. If you crash into a wall, your velocity drops to zero, and/or maybe there is some penalty.

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Different Approaches as a Sign of a Healthy Ecosystem

I find it a healthy sign at the end of semester when there are many different ways that students approach solving a problem. Most students took an energy approach here (which is very sensible), but plenty of students also took various kinematic approaches.

Below are just a sample of my students’ work although I was not the grader for this problem.

More experimenting in worked example layouts

This is the kind of strategy that I think is really important for my future physics teachers. I oscillate over the years about whether and how much to do this with students.

Screen Shot 2018-12-02 at 5.38.18 PM

I added a few more correct examples, just playing with different formats, and show-casing different strategies.

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