Maximum and effective value of alternating current (sine) The derivation of the relationship between maximum and effective value

Let the current of alternating current be I = I '* sin (WT)
If the current intensity is passed through R, the heat energy generated after a period is Q '= (1 / 2) * I' ^ 2 * r * t, which can be obtained by integrating in the interval 0 ~ t
The equivalent current I is defined as the DC current needed to generate the same heat energy as above through resistance R in time T. q = I ^ 2 * r * t
Q=Q'
So I = 0.7071 * I '

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