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An alternating current is given by \(I={I}_{A}\sin \omega t+{I}_{B}\cos \omega t\). The r.m.s current will be

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An alternating current is given by \(I={I}_{A}\sin \omega t+{I}_{B}\cos \omega t\). The r.m.s current will be

a

\(\frac{\sqrt{{I}_{A}^{2}+{I}_{B}^{2}}}{2}\)

b

\(\frac{\left|{I}_{A}+{I}_{B}\right|}{\sqrt{2}}\)

c

\(\sqrt{{I}_{A}^{2}+{I}_{B}^{2}}\)

d

\(\sqrt{\frac{{I}_{A}^{2}+{I}_{B}^{2}}{2}}\)

✓ Correct answer: d)

\(\sqrt{\frac{{I}_{A}^{2}+{I}_{B}^{2}}{2}}\)

Explanation

Given the current as \(I={I}_{A}\sin \omega t+\) \({I}_{B}\cos \omega t\), the r.m.s. current is calculated by integrating the square of the current over time, then taking the square root. i.e.,

\({i}_{ms}=\sqrt{\frac{\int {I}^{2}dt}{\int dt}}\\ {I}_{rms}=\sqrt{\frac{{I}_{A}^{2}+{I}_{B}^{2}}{2}}\)

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