A.c fundamentals, circuits and circuit theory questions with answers
95 multiple-choice questions. Open any question for its answer and explanation.
- All definitions of power factor of a series R-L-C circuit are correct except
- In a parallel R-C circuit, the current always _________the applied voltage
- Wire-wound resistors are unsuitable for use at high frequencies because they
- What will be the phase angle between two alternating waves of equal frequency, when one wave attains maximum value the other is at zero value?
- The series and parallel resonance on L-C circuit' differs in that
- Power factor of an inductive circuit is usually improved by connecting capacitor to it in
- The period of a sine wave is ___________ seconds. Its frequency is
- Which of the following circuit component opposes the change in the circuit voltage ?
- In an AC. circuit, a low value of kVAR compared with kW indicates
- The input of an
- Time constant of an inductive circuit
- The r.m.s. value of a sinusoidal
- If a sinusoidal wave has frequency of 50 Hz with 30 A r.m.s. current which of the following equation represents this wave?
- If two sine waves of the same frequency have a phase difference of JT radians, then
- Capacitive reactance is more when
- At __________ frequencies the parallel R-L circuit behaves as purely resistive.
- Skin effect occurs when a conductor carries current at _________ frequencies.
- In a pure inductive circuit if the supply frequency is reduced to $$\frac{1}{2},\,$$ the current will
- Inductance of a coil Varies
- The r.m.s. value of pure cosine function is
- Power factor of electric bulb is
- In a purely inductive circuit
- A heater is rated as 230 V, 10 kW,
- In a pure resistive circuit
- The voltage of domestic supply is 220 V. This figure represents