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Root Mean Square

  1. Mar 25, 2016 #1
    What is the root mean squad (RMS) of a signal (or wave) and why is it important for electrical engineering?

    How do you Find it?

    What is it used for?

    Thank You All
  2. jcsd
  3. Mar 25, 2016 #2

    Buzz Bloom

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    Gold Member

    Hi Puglife:

    I think the following will help you with respect tp both method and utility.

    I recommend that a good general practice is to see what Wikipedia says about a topic as a way of getting started to understand it.

  4. Mar 25, 2016 #3


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    RMS is just what it sounds like. The Root of the Mean of the Squares. In any waveform including a solid DC line if we sample the voltage at points along the waveform, square each one, average them all together, and then take the square root of that average we will have the RMS value. You shouldn't have to look very hard to see that the RMS of DC is the DC voltage. For a sine wave the RMS is always the peak voltage divided by the square root of 2. The RMS voltage is naturally a type of average and in the case of electronics an RMS voltage will dissipate the same amount of heat in a resistor as the same DC voltage. For example, 10 volts DC will produce the same heat in a resistor as 10 volts AC RMS.
  5. Mar 25, 2016 #4
    Thank you, that makes total sense, so im assuming to find the rms you take the square root of the integral of the function at squared with respect to the independent variable?
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