As the frequency of an ac circuit increases, the current first increases and then decreases. What combination of circuit elements is most likely to comprise the circuit? (a) Inductor and capacitor. (b) Resistor and inductor. (c) Resistor and capacitor. (d) Resistor, inductor and capacitor.
Correct option is C) Impedance of an LCR ciorcuit is given by Z=R2+(Xl−XC)2 =R2+(2πυL−2πυC1)2 The variation of Z with υ is shown in the figure. As υ increases , Z decreases and hence current increases. At υ=υr, Z is minimum , current is maximum . Beyond υ=υr , Z increases and current decreases. Hence , the combination of circuit elements is most likely to comprise the circuit are R, L and C .
