Alternating Current and Voltage Questions and Answers
Alternating Current (AC) and Voltage are the backbone of electrical and electronic systems. Understanding their behavior, waveforms, and phase relationships is essential for solving circuit problems. Competitive exams like GATE, SSC JE, and DRDO often include aptitude questions and answers based on RMS value, frequency, and power calculations. Practicing these questions with detailed explanations enhances analytical and calculation skills. Build your confidence by solving aptitude test questions and downloading AC circuit PDFs for quick revision.
Explore questions on AC voltage concepts and applications. Related topics like electrical current and Ohm's law and voltage regulators can deepen your knowledge.
Alternating Current and Voltage
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7 questions
1. In both induction and synchronous ac motors
- the operating speed is very steady
- the stator magnetic field is stationary
- the stator magnetic field rotates
- the "squirrel cage" forms the rotor
2. Most practical alternators generate electricity from
- a coil rotating within a magnetic field
- a magnetic field rotating around fixed windings
- a permanent magnet rotating within a varying electromagnetic field
- none of the above
3. A half-cycle average voltage of 12 V is equal to what rms voltage?
- 13.33 V
- 8.48 V
- 18.84 V
- 7.64 V
4. A rectangular wave that has a duty cycle of 50% could be called a
- "c" wave
- sawtooth wave
- square wave
- triangular wave
5. The effective value of a sine wave is equal to
- 0.707 of peak voltage
- 0.636 of peak voltage
- sin 45° of peak voltage
- both 0.707 of peak voltage and sin 45° of peak voltage
6. What is the fourth harmonic of a fundamental frequency of 400 Hz?
- 100 Hz
- 4 kHz
- 4 Hz
- 1.6 kHz
7. that is the average voltage when a rectangular wave's base line voltage is 20 V, its peak-to-peak voltage is 50 V, and its duty cycle is 20%?
- 26 V
- 30 V
- 40 V
- 45 V