Physics Cup – TalTech 2026 – Problem 3

By Jaan Kalda

At time t=0, a constant voltage V\equiv V_0 is applied between nodes A and B of the infinite circuit shown below. All inductors have inductance L, and all capacitors have capacitance C. Find the input current I(t) as a function of time.

Please submit the solution to this problem via e-mail to physcs.cup@gmail.com. After the publication of the first hint, the base score is reduced to 0.9 pts. For full regulations, see the “Participate” tab.