EECS 210_________________________PROBLEM SET #5________________________Winter 2001

**ASSIGNED:** February 09, 2001. **Read:** Chapter 5 of text and Chapter 1 of Additional Course Notes.

**DUE DATE:** February 16, 2001. **In Lab Book:** Read material on the Lab Exam, which is THIS WEEK.

**THIS WEEK:** Thevenin and Norton equivalents and maximum power transfer.

- Text #4.55. EXTRA: See Additional Course Notes, pages 54-55, for more automobile loads.
- Text #4.58. 1 node equation in 1 unknown for each of V
_{OC} and I_{SC}.
Note (b) is a check on (a).
- Text #4.62. HINT: Simplify the leftmost 3 elements and do a Thevenin-to-Norton xform.
- Text #4.69. Apply a 1V voltage source and compute current (1 node equation in 1 unknown).

- Text #4.71a. The basic idea behind maximum power transfer--what it is and what it
*isn't*.

Now *redo* this problem with the 6 Ohm resistor and variable R_{o} exchanged (R_{o} is now the load).
- For #4.62, what load resistance connected to terminals a-b dissipates the most power?

Why bother with Thevenin equivalents? Try this problem with a *nonlinear* device:

We wish to compute the voltage and current for the 96-watt light, which is NOT a resistor!

- Compute the Thevenin equivalent of the circuit connected to ("seen by") the light.
- Use KVL to obtain a
*quadratic* equation for the current through the light (or its voltage).
- Compute the voltage and current for the light. Note there are
**two** correct answers!

HINT: Regard the 96-watt light as having the *nonlinear* i-v characteristic i=96/V.

"The difference between a halo and a noose is about one foot"