Unit 17: Alternating Current — Mcqs

MCQ17.1.Name of device that is used as a part of charging circuit for mobile phones is:

MCQ17.2.A 10 μF capacitor is plugged into a 110 V_rms, 60 Hz voltage source, with an ammeter in series. The value of I_rms that passes through the capacitor is:

MCQ17.3.In an RC-circuit a 10 kΩ resistance is connected in series to a capacitor of 0.05 μF. The applied voltage for charging is 36 V, the RC-time constant to charge capacitor is:

MCQ17.4.In a purely inductive or capacitive circuit, the average power consumed is:

MCQ17.5.Through which of the AC-circuit elements both emf and current are in phase?

MCQ17.6.An inductor with a reactance of 120 Ω, a capacitor with a reactance of 150 Ω and a 24 Ω resistance are connected in series across a 220 V source. When the circuit is at resonance, then voltage across the inductor is:

MCQ17.7.If magnetic field is doubled in an inductor, then, magnetic energy density becomes:

MCQ17.8.RC-time constant is measured in:

MCQ17.9.Resonance frequency of RLC-series circuit is f_r. If the capacitance is made 4 times the initial value, then the resonance frequency becomes:

MCQ17.10.The magnitude of mutual inductance M between two coils when current changes at 20 A s⁻¹ in one coil induces an emf of 50 mV in the other is: