Q.

An inductor of inductance L, a capacitor of capacitance C and a resistor of resistance 'R' are connected in series to an AC source of potential difference 'V' volts as shown in the figure.

Potential difference across L, C and R is 40 V, 10 V and 40 V, respectively. The amplitude of current flowing through the LCR series circuit is 102A. The impedance of the circuit is                      [2021]

1 5 Ω  
2 42 Ω  
3 52 Ω  
4 4 Ω  

Ans.

(1)

Given, VL=40V

VC=10V,  VR=40V

Vrms=VR2+(VL-VC)2Vrms=402+(40-10)2=50V

I0=102A    Irms=I02=10A

Impedance, Z=VrmsIrms=5010=5 Ω