671. A wire of resistance R is coiled inductively so that its inductance is L. The impedance of the coil at a frequency of f is_______________?
A. (R+2πfL)
B. R+1/2πfL
C. (R2+f2L2)
D. (R2+4π2f2L2)

672. Ammeter connected in an AC circuit measures______________?
A. The exact value of the current
B. RMS value of the current
C. The net value of the current
D. The peak value of the current

673. When a pure inductor of inductance L and a pure capacitor of capacitance C are connected in parallel to a sinusoidal potential difference V the potential difference across both L & C will be_______________?
A. Same
B. Different
C. At L will be more than at C
D. At L will be less than at C

674. What is the self-inductance of a coil in which an induced emf of 2V is set up when the current changes at the rate of 4 As-1 ?
A. 0.5 mH
B. 0.5H
C. 2.0H
D. 8.0H

675. The frequency of a circuit consisting of a capacitance C and a resistor R is________________?
A. C/R
B. R/C
C. 1/RC
D. 1/ 2RC

676. A 10Ω electric heater is connected to a 220V 50Hz mains supply. What is the peak value of the potential difference across the heater element ?
A. 220V
B. 220/ 2V
C. 110V
D. 220 √2V

677. A choke is used as a resistance in_________________?
A. DC circuit
B. AC circuits
C. Both AC and DC circuit
D. Full wave rectifier circuit

678. At resonance the value of the power factor in an L-C-R series circuit is_______________
A. Zero
B. 2
C. 1
D. Not definite

679. An A.C series circuit containing 4Ω resistance and 3Ω inductive reactance. The impedance of the circuit is______________?
A. 1Ω
B. 5Ω
C. 7Ω
D. 7Ω

680. An inductive coil has a resistance of 100Ω. When an AC signal of frequency 1000Hz is fed to the coil the applied voltage leads the current by 45Ω. What is the inductance of the coil ?
A. 10mH
B. 12mH
C. 16mH
D. 20mH

NOTE
IF YOU THINK ANY OF THE MCQ ABOVE IS WRONG.
PLEASE COMMENT WITH CORRECT ANSWER AND ITS DETAIL EXPLANATION IN COMMENT BOX.
THANK YOU