JEE Mains · Physics · STD 12 -7. Alternating current
A alternating current at any instant is given by \(i=\left[6+\sqrt{56} \sin \left(100 \pi t+\frac{\pi}{3}\right)\right] A\). The rms value of the current is _________ A.
- A \(5\)
- B \(6\)
- C \(7\)
- D \(8\)
Answer & Solution
Correct Answer
(D) \(8\)
Step-by-step Solution
Detailed explanation
\(I_{\text {rms }}=\sqrt{\frac{\int i^2 d t}{\int d t}}\) \(I_{\text {rms }}=\sqrt{(6)^2+\frac{(\sqrt{56})^2}{2}}\) \(=\sqrt{36+28}\) \(=\sqrt{64}\) \(=8 \mathrm{~A}\)
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