1. The problem statement, all variables and given/known data http://imageshack.us/a/img831/8798/homeworkprobsg31.jpg [Broken] Assuming that the switch has been in position #1 for a long time; at t = 0 the switch is moved to position #2. Calculate the current i(t) for t>0. 2. Relevant equations Q = CV V = IR V(t) = -V0*e-t/RC (V0 is the capacitor voltage at time t = 0) some formula I am probably forgetting 3. The attempt at a solution I did not get that well in to RC circuit problems before so please bare with me, even though I sort of know how they work. I think the capacitor becomes fully charged, so no current goes across it, but charge is not given, so not sure how to determine Vc(t). At t=0, is the drop across the capacitor the same as the drop across the 3kΩ, since they are parallel elements? So doing KVL with the 6k and 3k only 12V - 6kΩ*i - 3kΩ*i = 0 then 12V = 9kΩ*i i = 0.00133A (1.33 mA) through the 3k resistor at t = 0 so if V = IR then V = (0.00133A)*(3000Ω) V = 4v across 3kΩ at t = 0 so then Vc(t = 0) = 4V ?? Not sure where to go from here, (if this is all is right so far). I can calculate the Q on the capacitor but not sure where I would use it then. I know the capacitor will then discharge current through the 6k and 3k if the switch goes to #2 but not sure what the formulas are for it. Sorry if there's something that's supposed to be right under my nose but I just can't seem to find / derive the proper formula anywhere.