Day 65: Constant Current Source Circuit Activity

I wanted my AP Physics 2 students to review the behavior of resistors in series and in parallel but from a new perspective. Inspired by the article “Experimenting with constant current and voltage sources” in The Physics Teacher, I provided students with solar panels instead of batteries and had them investigate how the voltage across and the current through the source changes when a second resistor is added in series or in parallel. I told them upfront that the solar cells were constant current devices. I should have left that unsaid and let them come to that conclusion on their own. Regardless, I hope that this introduction to solar cells will provide a hook when discussing the photoelectric effect next semester in our quantum unit.


The solar panels only function as constant current sources for a range of voltages and resistive loads. I need to investigate the best combination of light intensity and resistors to improve the outcome of this lab. Those groups investigating the effect of adding a resistor in parallel had good results, but the groups investigating the effect of adding a resistor in series did not.

  ##circuits ##setbacks ##paradigmlab  

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