This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Physics (Part I) Chapter 7 Alternating Current – Quiz 16 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Physics (Part I) Chapter 7 Alternating Current Quiz 16 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. On the oscilloscope the vertical axis represents A) Frequency. B) Time. C) Power. D) Voltage. Show Answer Correct Answer: D) Voltage. 2. The alternating current from a source is represented by I= 0.5sin314t. The frequency of ac is A) 314Hz. B) 100Hz. C) 50Hz. D) Zero. Show Answer Correct Answer: C) 50Hz. 3. The value of power factor for a purely resistive circuit A) 0. B) 1. C) -1. D) Phi. Show Answer Correct Answer: B) 1. 4. Consider the following statements and then select the correct Statements A) I is correct, II and III are incorrect. B) I III are correct, II is incorrect. C) I II are correct, III is incorrect. D) I, II and III are correct. Show Answer Correct Answer: D) I, II and III are correct. 5. In a step-up transformer, the turns ratio $N_{p}:N_{s}$ $1:10$ $230\, \text{V}$ $2\, \text{A}$ A) $20\, \text{A}$. B) $2\, \text{A}$. C) $0.2\, \text{A}$. D) $10\, \text{A}$. Show Answer Correct Answer: A) $20\, \text{A}$. 6. What is the duration of one cycle known as ..... A) Waveform. B) Peak value. C) Instantaneous value. D) Period. Show Answer Correct Answer: D) Period. 7. The household line voltage of ac measured is $220\, \text{V}$ A) $311\, \text{V}$. B) $220\, \text{V}$. C) $155\, \text{V}$. D) $440\, \text{V}$. Show Answer Correct Answer: A) $311\, \text{V}$. 8. Which component in an AC circuit is used to change the voltage level? A) Capacitor. B) Transformer. C) Resistor. D) Inductor. Show Answer Correct Answer: B) Transformer. 9. The opposition to AC current flow presented by capacitors and inductors is called: A) Resistance. B) Reactance. C) Impedance. D) Reluctance. Show Answer Correct Answer: B) Reactance. 10. Which of the following is a disadvantage of a single-phase system compared to a three-phase system? A) Higher efficiency. B) More complex design. C) Less power capacity. D) Requires more conductors. Show Answer Correct Answer: C) Less power capacity. 11. In an AC circuit, if the voltage is given by v=8.0 sin(500t), what is the peak voltage? A) 0 V. B) 16 V. C) 8.0 V. D) 4.0 V. Show Answer Correct Answer: C) 8.0 V. 12. Which of the following statements is correct about the phase lagging in a capacitive circuit? A) Current leads the voltage. B) Voltage leads the current. C) Voltage leads the resistance. D) Resistance leads the current. Show Answer Correct Answer: A) Current leads the voltage. 13. Apa yang terjadi apabila Xl lebih nesar dari pada Xc A) Rangkaian akan bersifat sepertiinduktor. B) Rangkaian akan bersifat sepertiisolator. C) Rangkaian akan bersifat sepertikapasitor. D) Rangkaian akan bersifat seperti resistor. Show Answer Correct Answer: A) Rangkaian akan bersifat sepertiinduktor. 14. Resonance happens in the AC circuit when this condition met ..... A) X$_{L}$= R. B) X$_{c}$= R. C) X$_{L}$= X$_{c}$. D) R=0. Show Answer Correct Answer: C) X$_{L}$= X$_{c}$. 15. What is the significance of the phase difference in AC circuits? A) The phase difference determines the frequency of the circuit. B) The phase difference only affects the voltage level. C) The phase difference in AC circuits is significant as it affects the power factor and the efficiency of power usage. D) The phase difference has no impact on circuit safety. Show Answer Correct Answer: C) The phase difference in AC circuits is significant as it affects the power factor and the efficiency of power usage. 16. If a student touches a live AC wire with wet hands, what could happen and why? A) Nothing will happen because AC is safe. B) The student could get a severe electric shock because water increases conductivity. C) The student will only feel a mild tingling. D) The student will be protected by the wire insulation. Show Answer Correct Answer: B) The student could get a severe electric shock because water increases conductivity. 17. At resonance RLC series circuit shows the behavior of: A) Pure resistive circuit. B) Pure capacitive circuit. C) Pure inductive circuit. D) Pure RLC circuit. Show Answer Correct Answer: A) Pure resistive circuit. 18. The AC voltage waveform is in the positive direction for some period of time and in the negative direction for some period of time. What is the name given to this waveform? A) Alternating wave. B) Inverted wave. C) Hertz wave. D) Sine wave. Show Answer Correct Answer: D) Sine wave. 19. Define root mean square (RMS) voltage. A) RMS voltage is the maximum voltage in a circuit. B) RMS voltage is the average of instantaneous voltages over one cycle. C) RMS voltage is the square root of the average of the squares of instantaneous voltages over one cycle. D) RMS voltage is the peak voltage divided by the square root of two. Show Answer Correct Answer: C) RMS voltage is the square root of the average of the squares of instantaneous voltages over one cycle. 20. The value of source frequency for which current amplitude is maximum A) 222.32 Hz. B) 550.52 Hz. C) 770Hz. D) 663.48Hz. Show Answer Correct Answer: D) 663.48Hz. 21. Define RMS current in the context of AC circuits. A) RMS current is the average value of an AC current over time. B) RMS current is the effective value of an AC current that delivers the same power as a DC current. C) RMS current is the maximum current that can flow in a circuit. D) RMS current is the peak value of an AC current. Show Answer Correct Answer: B) RMS current is the effective value of an AC current that delivers the same power as a DC current. 22. At what angles is the maximum emf generated during the rotation of a conductor? A) 45$^\circ$ and 135$^\circ$. B) 180$^\circ$ and 360$^\circ$. C) 90$^\circ$ and 270$^\circ$. D) 0$^\circ$ and 180$^\circ$. Show Answer Correct Answer: C) 90$^\circ$ and 270$^\circ$. 23. ASSERTION:IRON LOSS IS MINIMIZED USING LAMINATED COREREASON:LAMINATION OF CORE REDUCES EDDY CURRENTS A) BOTH ASSERTION AND REASON ARE TRUE AND REASON IS THE CORRECT EXPLANATION OF THE ASSERTION. B) BOTH ASSERTION AND REASON ARE TRUE AND REASON IS NOT THE CORRECT EXPLANATION OF THE ASSERTION. C) ASSERTION IS TRUE BUT REASON IS FALSE. D) ASSERTION AND REASON IS FALSE. Show Answer Correct Answer: A) BOTH ASSERTION AND REASON ARE TRUE AND REASON IS THE CORRECT EXPLANATION OF THE ASSERTION. 24. In an ac circuit, the effective voltage is A) Equal to the maximum instantaneous voltage. B) Greater than the maximum instantaneous voltage. C) Less than the maximum instantaneous voltage. D) None of the above. Show Answer Correct Answer: C) Less than the maximum instantaneous voltage. 25. What is phase difference between voltage and current in LCR series circuit at resonance? A) 45$^{o }$. B) 0$^{o}$. C) 90$^{o}$. D) 30$^{o }$. Show Answer Correct Answer: B) 0$^{o}$. ← PreviousNext →Related QuizzesClass 12 Physics (Part I) Chapter 7 Alternating Current Quiz 1Class 12 Physics (Part I) Chapter 7 Alternating Current Quiz 2Class 12 Physics (Part I) Chapter 7 Alternating Current Quiz 3Class 12 Physics (Part I) Chapter 7 Alternating Current Quiz 4Class 12 Physics (Part I) Chapter 7 Alternating Current Quiz 5Class 12 Physics (Part I) Chapter 7 Alternating Current Quiz 6Class 12 Physics (Part I) Chapter 7 Alternating Current Quiz 7Class 12 Physics (Part I) Chapter 7 Alternating Current Quiz 8Class 12 Physics (Part I) Chapter 7 Alternating Current Quiz 9Class 12 Physics (Part I) Chapter 7 Alternating Current Quiz 10 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books