Page 112 - Schaum's Outline of Theory and Problems of Electric Circuits

Waveforms and Signals

6.1 INTRODUCTION
The voltages and currents in electric circuits are described by three classes of time functions:

(i) Periodic functions
(ii) Nonperiodic functions
(iii) Random functions

In this chapter the time domain of all functions is 1 < t < 1 and the terms function, waveform, and
signal are used interchangeably.

6.2 PERIODIC FUNCTIONS
A signal vðtÞ is periodic with period T if
vðtÞ¼ vðt þ TÞ for all t
Four types of periodic functions which are specified for one period T and corresponding graphs are
as follows:
(a) Sine wave:
v ðtÞ¼ V sin 2 t=T ð1Þ
1
0
See Fig. 6-1(a).

Fig. 6-1(a)

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