COMEDK · Physics · 23. Alternating Current
If instantaneous current is given by \(i=4 \cos (\omega t+\phi)\), then the rms value of current is
- A \(2 \sqrt{2} \mathrm{~A}\)
- B \(4 \mathrm{~A}\)
- C \(4 \sqrt{2} \mathrm{~A}\)
- D zero
Answer & Solution
Correct Answer
(A) \(2 \sqrt{2} \mathrm{~A}\)
Step-by-step Solution
Detailed explanation
Instantaneous current, \[ i=4 \cos (\omega t+\phi) \] Comparing with standard equation, \(i=i_{0} \cos (\omega t+\phi)\), we get \(\therefore\) Peak current, \(i_{0}=4 \mathrm{~A}\)…
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