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Hold Still Please

Can you arrange a set of charged particles so that none of them start to move when released from rest?


Age 16 to 18
Challenge Level


infinite ladder of resistances
Each resistance in this infinite network is 1 ohm. The 'ladder' extends indefinitely to the right.
Find the total resistance between A and B.

You do not need to know any physics to do this problem. If you read the notes you will see how to write down equations for resistances of networks.