Question
Write the definition of root mean square value of alternating current.
✓
Answer
The square root of the mean square of the instantaneous value of alternating curent is called the root mean square value $I_{ rms }$ of the current.
$I ^2= I _0^2 \sin ^2 \omega t$
$I _{ rms }=\frac{ I _0}{\sqrt{2}}$ or $I _{ rms }=0.707 I _0$
Root mean square value of ac current is obtained by multiplying its peak value by $\frac{1}{\sqrt{2}}$ or 0.707
$I ^2= I _0^2 \sin ^2 \omega t$
$I _{ rms }=\frac{ I _0}{\sqrt{2}}$ or $I _{ rms }=0.707 I _0$
Root mean square value of ac current is obtained by multiplying its peak value by $\frac{1}{\sqrt{2}}$ or 0.707
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