Here’s the link: https://www.desmos.com/calculator/ii99lugy3i
About a year ago, when I started participating more in physics teacher communities online, I came across some circuit diagrams that were laid out to emphasize the common “electric potential is like height” metaphor. They took a single-loop circuit and sort of “unwrapped” it to show the constant potential of connecting wires and the potential drops that occurred across the resistors or other elements.
I don’t know if there’s a common name for these, and I haven’t seen all that many of them around, but I think I like them. I’m going to try having students sketch these diagrams during circuit analysis, once we’re back at school and covering new material again.
So in this Desmos graph you can adjust the battery’s emf as well as the three resistances. There’s a “classic” diagram you can display, or not, as seen at the right. But when you adjust the circuit’s properties the height-based diagram will dynamically rescale itself to show the magnitudes of the potential drops for each resistor.
Ideas that I hope this graph can emphasize for learners:
- changes in potential occur only within the non-wire elements (in the idealized case of wires with no resistance, of course)
- the relative sizes of the resistances map to the relative sizes of the potential drops
- changing the battery’s emf scales the potential differences up/down, but doesn’t impact their relative size
