# Voltage dependent Current source

1. May 18, 2013

### xlu2

1. The problem statement, all variables and given/known data

Find Vout at t=0.782s (I already found Vout at t=0 s. It is 0 V.)

2. Relevant equations
V=IR

3. The attempt at a solution
First I found Vs = 9*sin(14*0.782)=-8.989817V (with t in radians)
Since Rpi is in parallel with the Vs, its voltage Vpi also equals to -8.98917 V.
Since the dependent source is I=10^-3*Vpi= -8.989817E-3 A, it is the same current traveling through the 1000 ohms resistor in the right loop.
Using the equation: Vout=IR=8.989817E-3A*1000ohms=8.990V (Current is positive in this case since the current direction is opposite of the passive configuration. That is, it is going from - to + instead of + to -.)

Apparently, my answer is wrong. Would any one please help me to see where I am doing wrong here? (I wonder how does the wire connect the two loops affect the situation. Is it possible that the R in Vout=IR is not 1000, but 1050 (50 ohms resistor in the left loop since both resistors might be in series?)

Many thanks in advance!

Last edited: May 18, 2013
2. May 18, 2013

### barryj

I tend to agree with you. The question did ask for V at t = 0 and at .782 msec. Did you submit both answers? The connecting wire will make no difference.

3. May 18, 2013

### xlu2

Yes

Thanks barryj.

Yes, I submitted 0 for t=0 s and it is correct.

The only problem I have is Vout when t=0.782s.

4. May 19, 2013

### xlu2

Problem solved! Thanks everyone.

5. May 19, 2013

### barryj

What was the answer???

6. May 21, 2013