Given the circuit shown below, the switch moves from position 1 to position 2 at just before t=0.

Write out the KCL indicated in this circuit, in terms of the voltage (v{R,L,C}), source current (iS), R, C and L, for t > 0.

Your answer might look something like: C.d^2(v)/dt^2 + dv/dt + R.v = iS/L