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The power factor of an AC circuit having resistance (R) and inductance (L) connected in series and an angular velocity ω is
- R/ωL
- R/(R² + ω²L²)^(1/2)
- ωL/R
- R/(R² − ω²L²)^(1/2)
Correct answer: R/(R² + ω²L²)^(1/2)
Solution
The power factor in an AC circuit is defined as the ratio of the resistance to the impedance, which is the square root of the sum of the squares of resistance and inductive reactance. In this case, the impedance is represented as (R² + (ωL)²)^(1/2), making the correct option R/(R² + ω²L²)^(1/2).
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