What is $rms$ (root mean square) value? Write the formula of $rms$ current for an alternating current.
(N/A) The $rms$ (root mean square) value of an alternating current is defined as the square root of the mean of the squares of the instantaneous currents over one complete cycle.
It is also known as the virtual or effective value of the alternating current.
It represents the value of a steady direct current which,when passed through a resistor for a given time,produces the same amount of heat as the alternating current does in the same resistor and in the same time.
The formula for $rms$ current $(I_{rms})$ in terms of peak current $(I_0)$ is given by:
$I_{rms} = \frac{I_0}{\sqrt{2}} \approx 0.707 I_0$
It is also known as the virtual or effective value of the alternating current.
It represents the value of a steady direct current which,when passed through a resistor for a given time,produces the same amount of heat as the alternating current does in the same resistor and in the same time.
The formula for $rms$ current $(I_{rms})$ in terms of peak current $(I_0)$ is given by:
$I_{rms} = \frac{I_0}{\sqrt{2}} \approx 0.707 I_0$
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