Alternating current or emf measuring instruments measures its:
Correct answer: A. r.m.s. value
- A. r.m.s. value
- B. Peak value
- C. Average value
- D. None of the above
Explanation
The correct option, r.m.s. value, represents the root mean square value of alternating current or electromotive force. It's a measure of the effective or equivalent value of the alternating quantity, commonly used by AC measuring instruments because it reflects the true power and heating effects in AC circuits.
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About Alternating Current
Alternating current varies periodically, so phase relationships become essential when current passes through a resistor, capacitor or inductor. The chapter distinguishes resistance from capacitive and inductive reactance, explains phase lead and lag, and connects changing electric and magnetic fields with the production and properties of electromagnetic waves.
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