Recently I have been investigating the frequency response of galvanometers. These are direct-current devices used to measure small currents. By using a low-frequency function generator to supply the alternating–current signal and a stopwatch smartphone app to measure the period, I was able to take data to allow a resonance curve to be drawn. This is the sort of project that should provide a fascinating research experience for the introductory physics student. In this article I will discuss the galvanometers that I used in this work, and will show a resonance curve for one of them.

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