Ok so I have some topic overview questions. I think I am on the right track but would like to make sure I am thinking about this the correct way. When I say time variant I simply mean there is a simple switch in the circuit. This is link to a were I found my supplemental material and it has a switch like I am talking about. http://www.allaboutcircuits.com/vol_1/chpt_16/2.html Question 1: Under what conditions does a Capacitor act like (A) an open circuit? (B) a short circuit? (C) a voltage source? Question 2: Under what conditions does an Inductor act like (A) a short circuit? (B) an open circuit? (C) a current source? MY ANSWERS: 1a) at t=0- because initially fully discharged thus empty and open circuit 1b) at t=0+ because the V across would be 0 thus short circuit 1c) at ∞ because capacitors remember/store voltage thus voltage source 2a) at t=0- because initially like nothing is there thus short circuit 2b) at t=0+ because the I across would be 0 thus an open circuit 2c) at ∞ because inductors remember all current sources thus would act like a current source SOME ADDITIONAL QUESTIONS: When we look at initial-final response equations: y(t)=yF + (yi - yF)e-t/τ y=v,i as asked fot yi=y(0+) yF=y(∞) τ= RC or L/R depending on the circuit 3) How do you find y(0+) for a capacitor? 4) How do you find y(0+) for current through an inductor? 5) How do you find y(0+) for voltage on a resistor? 6) How do you find y(∞)? I do not know the answer to 3-6. I am obviously kind of confused when it comes to the addition of the on/off switch into the circuit network. HELP on the 0+, 0- and ∞ times would be great!