G. Rizzoni, Principles and Applications of Electrical Engineering
Problem solutions, Chapter 6
Chapter 6 Instructor Notes
Chapter 6 has also seen substantive revisions with respect to the Third Edition.
A section on
Fourier analysis has been added (Section 6.2), and the material on Bode plots has been expanded (Section
6.4). The material on Laplace transforms has been moved to the Appendix B.
These changes were
prompted by comments and suggestions made by numerous users. Chapter 6 can be covered immediately
following Chapter 4, or after completing Chapter 5.
There is no direct dependence of Chapter 6 on Chapter
After the first section briefly introduces the notion of sinusoidal frequency response and motivates
the use of sinusoidal signals, the Fourier Series method of representing signals is described in detail in
Further, the text and examples also illustrate the effect of a multi-components signal
propagating through a linear system.
Four examples accompany this presentation.
Instructors who use this
material will find some computing tools available on the website that will assist the students in developing
an intuitive understanding of Fourier series.
Section 6.3 introduces filters, and outlines the basic characteristics of low-, high- and band-pass
The concept of resonance is treated in greater depth than in the previous edition, and a connection is
made with the natural response of second order circuits, which may be useful to those instructors who have
already covered transient response of second-order circuits. Four detailed examples are included in this
Further, the boxes
Focus on Measurements: Wheatstone bridge filter
Measurements: AC line interference filter
(pp. 303-305), and
Focus on Measurements: Seismic
(pp. 305-308) touch on additional application examples.
The first and last of these
boxes can be linked to related material in Chapters2, 3, and 4.
The instructor who has already introduced the operational amplifier as a circuit element will find
that section 8.3, on active filters, is an excellent vehicle to reinforce both the op-amp concept and the
frequency response ideas.
Another alternative (employed by this author) consists of introducing the op-
amp at this stage, covering sections 8.1 through 8.3.
Finally, Section 6.4 expands the previous coverage of Bode plots, and illustrates how to create
approximate Bode plots using the straight-line asymptotic approximation. The box
Focus on Methodology:
clearly outlines the method, which is further explained in two examples.
The homework problems present several frequency response, Fourier Series, filter and Bode plot
exercises of varying difficulty.
The instructor who wishes to use one of the many available software aids
(e.g., MATLAB® or Electronics Workbench® ) to analyze the frequency response of more complex
circuits and to exploit more advanced graphics capabilities, will find that several advanced problems lend
themselves nicely to such usage. More advanced problems could be used as a vehicle to introduce modern