An alternating current is given by the equation i = i1 sin $\omega$t + i2 cos $\omega$t. The rms current will be :
Solution
${I_0} = \sqrt {I_1^2 + I_2^2 + 2{I_1}{I_2}\cos \theta }$<br><br>${I_0} = \sqrt {I_1^2 + I_2^2 + 2{I_1}{I_2}\cos 90^\circ }$<br><br>${I_0} = \sqrt {I_1^2 + I_2^2 + 2{I_1}{I_2}(0)} = \sqrt {I_1^2 + I_2^2}$<br><br>We know that,<br><br>${I_{rms}} = {{{I_0}} \over {\sqrt 2 }}$<br><br>So, ${I_{rms}} = {{\sqrt {I_1^2 + I_2^2} } \over {\sqrt 2 }}$
About this question
Subject: Physics · Chapter: Alternating Current · Topic: AC Circuits: R, L, C
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