An AC source rated 220 V, 50 Hz is connected to a resistor. The time taken by the current to change from its maximum to the rms value is :
Solution
$I = {I_0}\sin \omega t$
<br><br>$\Rightarrow$ ${{{I_M}} \over {\sqrt 2 }} = {I_M}\sin \omega t$
<br><br>$\Rightarrow$ $\omega t = {\pi \over 4}$
<br><br>$\Rightarrow$ $t = {\pi \over {4\omega }}$ $= {\pi \over {4\left( {2\pi f} \right)}}$
<br><br>$\Rightarrow$ t = ${1 \over {8 \times 30}} = {1 \over {400}}$ = 2.5 ms
About this question
Subject: Physics · Chapter: Alternating Current · Topic: AC Circuits: R, L, C
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