What is root mean square value (R.M.S)?

What is root mean square value (R.M.S)?
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1 Answer

Answer :

The R.M.S value is also known as effective value or virtual value. The instantaneous value of both the directions will all be squared up and will be added together. Then divide to get the average with the number of instantaneous values and find the square root of this average to calculate the R.M.S value of the emf or current.

Or

The R.M.S value of an alternating current or emf is equal to the same value of direct current (DC), which produces the same amount of heat with the same time when applied the DC through the same circuit as AC is produced.

R.M.S value = maximum value / √2 = 1/√2 = 0.707.
∴ R.M.S value or effective value = 0.707 * Emax or Imax
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