Here’s a systematic approach to simplify a complicated resistor network by looking for series and parallel resistor patterns.

Created by Willy McAllister.

Simulation model

  • This circuit has the voltage source set to 3V.
  • Compute the equivalent resistance, R_equiv, of the resistor network.
  • Compute the current provided by the voltage source.
  • Click on DC to run a simulation.
  • Compare your answer to the simulation.

  • Challenge: Build a circuit down lower on the page with a 3V source and a single R_equiv. Add a current probe (arrow). Click on DC to measure the current. Is it the same as the complicated circuit? It should be.

See also this article on how to simplify resistor networks.