This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction – Quiz 27 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 27 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. What is the principle behind an AC generator? A) Chemical reaction. B) Mechanical friction. C) The principle behind an AC generator is electromagnetic induction. D) Thermal expansion. Show Answer Correct Answer: C) The principle behind an AC generator is electromagnetic induction. 2. Click Forward and wait until the magnet gets to the top. How many field lines are passing through the loop now? A) 0. B) 5. C) 10. D) 15. Show Answer Correct Answer: C) 10. 3. The current passing through a choke coil of self inductance 5 H is decreasing at the rate of 2 A/s. The e.m.f.developed across the coil is A) 5. B) -5. C) 10. D) -10. Show Answer Correct Answer: C) 10. 4. Doubling the diameter of a loop of wire produces, what will happen for emf, assuming all other factors are constant A) Emf will increase to double. B) Emf will decrease to half. C) Emf will increase to four time. D) Emf will decrease to quarter. Show Answer Correct Answer: C) Emf will increase to four time. 5. Define magnetic flux and its unit. A) Magnetic flux is measured in Webers (Wb). B) Magnetic flux is measured in Teslas (T). C) Magnetic flux is measured in Amperes (A). D) Magnetic flux is defined as the force exerted by a magnet. Show Answer Correct Answer: A) Magnetic flux is measured in Webers (Wb). 6. What causes the potential difference to be induced in the wire? A) The temperature of the wire. B) The strength of the electric current. C) The movement of the wire through a magnetic field. D) The length of the wire. Show Answer Correct Answer: C) The movement of the wire through a magnetic field. 7. The function of a transformer is to ..... A) Raise and lower the apparent power levels. B) Transfer DC voltage from the primary winding to the secondary winding. C) Increase or decrease A.C voltage or A.C current levels. D) Transform mechanical energy into electrical energy. Show Answer Correct Answer: C) Increase or decrease A.C voltage or A.C current levels. 8. The direction of the induced current in a conductor moving through a magnetic field can be determined using A) Faraday's law. B) Current rule. C) Fleming's right-hand rule. D) Fleming's left-hand rule. Show Answer Correct Answer: C) Fleming's right-hand rule. 9. The core of a transformer is laminated to reduceeddy currentsresistive losseshysteresis losses A) 1, 2, 3. B) 1, 2. C) 1 only. D) 3 only. Show Answer Correct Answer: C) 1 only. 10. Which law states that the induced current is proportional to the change of magnetic flux? A) Lenz's law. B) Ampere's law. C) Faraday's law. D) Gauss' law. Show Answer Correct Answer: C) Faraday's law. 11. What happens to the induced emf when the speed of movement increases? A) Induced emf becomes zero. B) Induced emf decreases. C) Induced emf remains constant. D) Induced emf increases. Show Answer Correct Answer: D) Induced emf increases. 12. A circular loop is placed in a decreasing magnetic field. What happens to the induced current in the loop? A) It flows clockwise. B) It flows into the page. C) It flows counterclockwise. D) It remains zero. Show Answer Correct Answer: A) It flows clockwise. 13. A current of 2.5 A flows through a coil of inductance 5 H. The magnetic flux linked with the coil is A) 0.5 Wb. B) 12.5 Wb. C) Zero. D) 2 Wb. Show Answer Correct Answer: B) 12.5 Wb. 14. Who is known for the invention of the motor, generator, and transformer? A) James Clerk Maxwell. B) Michael Faraday. C) Nikola Tesla. D) Thomas Edison. Show Answer Correct Answer: B) Michael Faraday. 15. Which component forms part of a d.c. motor but not a simple moving coil a.c. generator? A) The coil. B) The brushes. C) The magnet. D) The split-ring commutator. Show Answer Correct Answer: D) The split-ring commutator. 16. Explain the concept of mutual induction. A) Mutual induction is the process where a constant current in one coil induces a voltage in an adjacent coil. B) Mutual induction is the process where a changing current in one coil induces a voltage in an adjacent coil. C) Mutual induction is not related to electromagnetic fields. D) Mutual induction only occurs in parallel circuits. Show Answer Correct Answer: B) Mutual induction is the process where a changing current in one coil induces a voltage in an adjacent coil. 17. The dimension of R/L, L/R and RC are A) Frequency, time period and time period. B) Wavelength, Frequency, and time period. C) Frequency, time period and Amplitude. D) None of the above. Show Answer Correct Answer: A) Frequency, time period and time period. 18. What is mutual induction and how does it occur? A) Mutual induction occurs only in transformers with a fixed current. B) It is the process of a single coil generating a magnetic field without any current change. C) Mutual induction happens when two coils are connected in series with a battery. D) Mutual induction is the process where a changing current in one coil induces a voltage in another nearby coil. Show Answer Correct Answer: D) Mutual induction is the process where a changing current in one coil induces a voltage in another nearby coil. 19. Question 2 A) A. B) B. C) C. D) D. Show Answer Correct Answer: C) C. 20. The emf induced by motion of conductor across magnetic field is called A) Potential Difference. B) Electric potential. C) Variable emf. D) Motional emf. Show Answer Correct Answer: D) Motional emf. 21. The advantage of an alternating current supply is A) Alternating current is easier to generate. B) The voltage of the alternating current can be changed easily. C) The frequency of the alternating current can be changed easily. D) The power of the supply can be maintained at a constant value. Show Answer Correct Answer: B) The voltage of the alternating current can be changed easily. 22. What is the relationship between current and resistance (for a constant voltage)? A) Current is proportional to resistance. B) Current is inversely proportional to resistance. C) Current is proportional to the square of resistance. D) Current is proportinal to the square root of resistance. Show Answer Correct Answer: B) Current is inversely proportional to resistance. 23. How is e.m.f induced in a circuit according to Faraday's law? A) By changing the resistance of the circuit. B) By changing the area of the circuit. C) By changing the magnetic flux linking the circuit. D) By changing the temperature of the circuit. Show Answer Correct Answer: C) By changing the magnetic flux linking the circuit. 24. A 60 W lamp is connected to a 120 V RMS supply. What is the effective current through the lamp? A) 0.25 A. B) 0.50 A. C) 0.75 A. D) 1.0 A. Show Answer Correct Answer: B) 0.50 A. 25. If the rate of change of magnetic flux is zero, what will be the induced electromotive force? A) Zero. B) Constant. C) Negative. D) Positive. E) None of these. Show Answer Correct Answer: A) Zero. ← PreviousNext →Related QuizzesClass 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 1Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 2Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 3Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 4Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 5Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 6Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 7Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 8Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 9Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 10 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books