UNIVERSITY OF CALIFORNIA AT BERKELEY
EECS Department
EECS 40, Fall 2006
Prof. Chang-Hasnain
Homework #4
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Posted: 9/27/06
Due at 5 pm in 240 Cory on Wednesday, 10/4/06
Total Points: 100
Put (1) your name and (2) discussion section number on your homework.
You need to put down all the derivation steps to obtain full credits of the problems.
Numerical answers alone will at best receive low percentage partial credits.
No late submission will be accepted expect those with prior approval from Prof.
Chang-Hasnain.
First order RC circuits:
1. Hambley, P4.2 (8pt)
2. In the figure below, assume the capacitor is initially completely discharged.
Assume both switches are open. At t = 0s, S1 closes. (12pt)
a. Derive an expression for Vout(t) for t>0.
b. Assume that at 30ms, S2 closes. Derive a new expression for V out(t) for t>
30ms.
c. Plot a figure of Voltage vs. time from t = 0 to t = 50ms, labeling all key
points (value at switching point, 1 time constant values, value at infinity).
5k
10k
Vx
S1
S2
1uF
10V
2*Vx
DC steady state:
3. Hambley, P4.21 (10pt)
4. Hambley, P4.16 (10pt)
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Vout
UNIVERSITY OF CALIFORNIA AT BERKELEY
EECS Department
RL circuits:
5. Hambley, P4.31 (10pt)
RC and RL with general sources:
6. Hambley, P4.34 (10pt)
7. Hambley, P4.36 (10pt)
8. Hambley, P4.39 (10pt)
9. Repeat problem P4.39 replacing the source with 10sin(300t) + 20cos(600t).
Write the differential equation and solve. [Hint: Try a particular solution of the
form Asin300t + Bcos300t + Csin600t + Dsin600t.]" (10pt)
Second order circuits
10. Hambley, P4.43 (10pt)
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