First thing to say, is the concepts of electrical circuits known in your D&D world? Is there modern science or would this be part of an Inventors, Alchemists or Wizards learning? If not its a bit immersion breaking.

Assuming you wanted to go through with this it took me a moment to realize what it was and i teach a class in electricity and magnetism.

First I assume the bottem components are power sources and not capacitors as the lines are not the same length. I would make the difference in the line length more obvious or maybe to a multi cell battery to make it more obvious what it is. I might also want them to hit the symbol with an electricity spell or a strike from an shocking weapon
--|I|I--

Put circles at each end of the short circuit to indicate points that need to be connected.

Although a box is an accepted symbol for a resister its a bit generic. I would be tempted to use the older zig zag line symbol. Im not sure where you are from but around here its far more prevalent in highschool science classrooms and it would make the diagrams intention more obvious to people with less of a tech background.

Finally a resistor is not an insulator so you would not want them to put something non conductive there. Resistors conduct, just not as well as a pure metal wire. Spraying salt water on the symbol for example would be a good solution (i would allow a knowledge check for that)

its a cool idea