An infinite net is made of identical wires. The resistance between points 1 and 2 is r, and the resistance between points 1 and 3 is R. Find the resistance R14 between points 1 and 4.

We received many solutions to our January Challenge, Lore of the rings. We are pleased to recognize the following successful solvers:

Guidelines for contributors

Many thanks to all contributors and we hope to hear from many more of you in the future!

Note: we always welcome and appreciate reader-contributed original Challenges!

The solutions to the past Challenges can be found here: https://aapt.scitation.org/topic/collections/physics-challenge Please note that AAPT membership may be required to view the files.

Boris Korsunsky, Column Editor

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