root mean square value

[Bhuvanesh123]

i have learned what is rms value just before . its has been stated like"power dissipated with rms voltage is same power dissipated by equivalent dc voltage".i understand this point. Later question arose to me why we need rms value of signal and i accommodate myself that is to make analyses simple.

But i want strong answer why we are interested in Rms value.?

 

[Nasser750gx]

RMS is for Alternating current. DC voltage is stable, but AC keeps alternating, so you need to calculate an average.

 

[chuckey]

Rms gives you the heating power of a signal.
Frank

 

[betwixt]

Now you know what RMS is but think about AC, taken over a period of one or more cycles, what is it's average if you don't use RMS?

Brian.

 

[yavuzyaman]

Rms is a common measure for AC to determining the voltage over a period. Because voltage is changing with time periodically.
Otherwise instantaneous voltage would falsify you when you calculate energy and power of the signal.

-yavuz

 

[Bhuvanesh123]

Now you know what RMS is but think about AC, taken over a period of one or more cycles, what is it's average if you don't use RMS?

average gives zero so we are going for rms.Thank you

 

[FvM]

average gives zero so we are going for rms.

Yes. Averaged rectified value also works for AC measurement and is often used. But it's not equal to "heating power" (post #3) for distorted waveforms.