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Badger33

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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

When we look at initial-final response equations:

y(t)=y

y=v,i as asked fot

y

y

τ= RC or L/R depending on the circuit

3) How do you find y(0

4) How do you find y(0

5) How do you find y(0

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.

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)=y

_{F}+ (y_{i}- y_{F})e^{-t/τ}y=v,i as asked fot

y

_{i}=y(0^{+})y

_{F}=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!
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