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Unformatted text preview: signals may be represented by both sine and cosine forms, they are all converted to either cosine or sine for sake of uniformity. This also helps in reading their relative phase angles if all of them are same frequency. 78 EE1002 Introduction to Circuits and Systems Why sinusoids? Sinusoidal sources have many important applications. Electric power supply is sinusoidal in form. Sinusoidal signals have many uses in Radio communications. From Fourier analysis it is known that all periodic signals can be represented as sum of sinusoidal signals. Root‐mean‐square values If a periodic voltage v(t ) is applied across a resistor, then the power dissipated in it will be v 2 (t )
p(t ) R
Thus power also is a function of time. Energy dissipated in the resistor per one period is given by T T v 2 (t )
dt R
0 ET p (t )dt 0 The average power dissipated in the resistor will be: T Pavg 12
v (t )dt
T
T2
T
1 v (t )
ET 1
0 p(t )dt dt T T
T0 R
R
0 T 12
2 v (t )dt Vrms
T0 T Vrms Pavg 12
v (t )dt
T
0 2
Vrms R Vrms is...
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 Winter '14

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