A series AC circuit has a resistance of 4 Ω and a reactance of 3 Ω. The impedance of the circuit is
The impedance of an AC circuit is given by 
… (i), where R = resistance, X = impedance.
Given: Resistance R = 4 Ω and Impedance X = 3 Ω
Substituting these values in (i), we get
Impedance Z = 
= 5 Ω (Ans)
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