ELEC 101, Spring 2005
Prof. Rich Kozick

Homework 8

Date Assigned: Wednesday, March 9, 2005
Date Due: Wednesday, March 23, 2005

  1. Exams: Please recall from the course syllabus that we will have a take-home exam on March 21-23 that will be worth 5% of your grade. This take-home exam will include the topics that we have covered since Exam 1, beginning with nodal analysis in Chapter 2 and concluding with inductors, capacitors, and time constants in Chapter 3. This includes homework assignments 4, 5, 6, and 7. The take-home exam will not include sinusoidal frequency response. The exam will be made available on March 21, and it will be due in class at 2:00 PM on March 23.

    We will not have class on Monday, March 21, because I will be in Philadelphia at a conference.

    Recall also that we will have in-class Exam 2 on Wednesday, March 30, and this will be worth 12.5% of your grade. This exam will include the same topics as the take-home, plus sinusoidal steady-state analysis (phasors, frequency response, and filters).

  2. Reading: The relevant reading in the Bobrow text to supplement the class notes on sinusoids and phasors is Sections 4.1, 4.2, 4.3, and 5.1.

  3. Please solve the following questions on phasors and sinusoids.

    For each sine wave, find the phasor representation (in polar form), and sketch the phasor in the complex plane.
    $ 0.2 \cos ( 1000 t - 45^o ) $
    $ 7 \cos (10 t + 150^o) $

    For each phasor, express the corresponding sine wave as a time function, and sketch the sine wave versus time. Assume $\omega = 2 \pi 100$ rad/sec.
    $ \underline{v} = 7 \angle{0^o}$
    $ \underline{v} = 2 \angle{-90^o}$

    Find the magnitude of each complex number below.
    $ \underline{v}_1 = 1 + j1 $
    $ \underline{v}_2 = 3 - j4 $
    $ \underline{v}_1 + \underline{v}_2 $
    $ (\underline{v}_1) \cdot (\underline{v}_2) $

Thank you.