Alternating Current

An inductor may store energy in ________________? A. Its electric field B. Its coilsC. Its magnetic field D. Both electric and magnetic fields

Two identical coaxial circular loops carry equal currents in the same direction. If the loops approach each other the current in______________? A. Each increaseB. Each decrease C. Each remains the same D. One increases whereas that in the other decreases

A voltage V = V0 cos ωt is applied across a resistor of resistance R the average power dissipated per cycle in the resistor is given by___________? A. V√/√2R B. V/√2√RC. V02/√2R D. 2/√2√R

n an LCR series circuit, if V is the effective value of the applied voltage VR is the voltage across R VL is the effective voltage across L & Vc is the effective voltage across C then_______________? IA. V = VR+VL+VC B. V2 = VR2+VL2+VC2C. V2 = VR2+(VL-VC)2 D. V2 = VL2+(VR-VC)2

The phase angle between the voltage and the current in an AC circuit consisting of a resistance is______________? A. Zero B. 45° C. 90° D. 180°

Choose the correct statement. In the case of AC circuit ohms law holds for_______________? A. Peak values of voltage and current B. Effective values of voltage and current C. Instantaneous values of voltage and currentD. All of the above

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. 12mHC. 16mH D. 20mH

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

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

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