How to Calculate Root Mean Square(RMS) Value of Alternate Current - Formula, Example

Definition:

The Root Mean Square(R.M.S) value of an alternate current supply converts the electrical energy to thermal energy at an equal rate in a given resistance and the R.M.S. value is also called as effective value denoted by Irms, Ieff or Ii.

Example :

In a radio circuit, the a.c voltage across a resistor is given by v=8sin120.Calculate the RMS Alternate Current of the radio circuit.

Given :

I = 80sin200

To Find :

Root Mean Square Alternate Current

Solution :

I = 80sin200 I = 80 * 0.873297297 I = 69.8378376 Substitute the given values in the formula,

RMS Alternate Current Irms	= I / √2
	= 69.8378376 / 1.414213562
	= 49.38281