Spintronics Community Forum

How to test resistors?

Over on Kickstarter, there’s mention of issues with some resistors, that they start spinning too fast with very little resistance:
https://www.kickstarter.com/projects/upperstory/spintronics-build-mechanical-circuits/posts/3679868
On my copy, this definitely happens with one of my 500 ohm resistors. It seems to only happen after it’s been running for a bit, I suspect heat has something to do with it in addition to what Paul mentions.

But I also suspect the 50 ohm resistor in the Battery Pack is having the same issue, and would love to be able to verify that; the problem is that 50 ohms is so little resistance that doing that same test is already discharging quite quickly, and it’s a little hard to distinguish between the different speeds. Can someone post a video of a 50 ohm resistor discharging against the battery properly? Or suggest some other circuit to test that resistor without things getting scarily fast?

I figured it out! The Voltage Halver from Challenge 62 does the job nicely, slowing down normal operation to a reasonable speed so that you can see more clearly the abnormal operation.