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Question
A series AC circuit has a resistance of 4 Ω and a reactance of 3 Ω. The impedance of the circuit is
Options
5 Ω
7 Ω
12/7 Ω
7/12 Ω
Solution
5 Ω
The impedance of the circuit is given by
`Z =sqrt(R^2+ X^2`
`R =4Ω&X=3Ω`
`⇒ Z=sqrt4^2 + 3^2 = 5_Ω`
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