Significance of Average value of a AC signal

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spiky
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[SOLVED] Significance of Average value of a AC signal

Hello,
I would like to know the significance of average value in a AC circuit. Let's consider a sinusoidal ac source with only a resistor in the circuit. The rms value of voltage and current indicate the equivalent DC value which would dissipate the same heat in the same circuit. So on similar terms what will the average value signify ?

Thanks
 
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spiky said:
Hello,
I would like to know the significance of average value in a AC circuit. Let's consider a sinusoidal ac source with only a resistor in the circuit. The rms value of voltage and current indicate the equivalent DC value which would dissipate the same heat in the same circuit. So on similar terms what will the average value signify ?

Thanks

The average value of a signal is the DC component of the signal. In a sinusoidal wave the average value is zero.
 
ofcourse, but what will it be if only magnitude is considered ? . What will the average value represent in a full wave rectified signal ?
It certainly does not represent DC value as rms value does that.
 
The average value is just the DC offset of the AC signal. A sine wave signal can have a DC offset. For example, like this:

v(t) = 2.5V + 2.5V cos(wt)
 
This has a good explanation of both and also a comparison and why some applications use RMS and others use just average

http://www.allaboutcircuits.com/vol_2/chpt_1/3.html
 
spiky said:
ofcourse, but what will it be if only magnitude is considered ? . What will the average value represent in a full wave rectified signal ?
It certainly does not represent DC value as rms value does that.

No, rms represents the value of a DC source that would output the same power as the sinusoidal source.
A rectified wave can be thought as the combination of a DC source (the mean value) and an infinite number of sinusoids with frequencies that are the harmonics of the original sinusoid. The Fourier series of the wave shows exactly this.