This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction – Quiz 4 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 4 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. At the instant when the current is 9.0 A, a magnetic flux of 2.5 $\times10^{-3}$ A) 10.3 J. B) 11.3 J. C) 22.5 J. D) 40.5 J. Show Answer Correct Answer: B) 11.3 J. 2. Electric currents produce ..... A) Electron clouds. B) Magnetic fields. C) Sound waves. D) Light waves. Show Answer Correct Answer: B) Magnetic fields. 3. In a generator, how can we increase the induced current? A) Move the conductor faster through the magnetic field. B) Use a weaker magnetic field. C) Decrease the number of turns in the coi. D) Use a thinner wire. Show Answer Correct Answer: A) Move the conductor faster through the magnetic field. 4. According to the Right Hand Rule, where is the magnetic field generated around a current-carrying wire? A) Perpendicular to the wire. B) Parallel to the wire. C) All the above. D) None of the above. Show Answer Correct Answer: A) Perpendicular to the wire. 5. Describe the factors affecting the induced emf in a coil. A) The color of the coil affects the induced emf. B) The temperature of the surrounding air influences the induced emf. C) The length of the wire used in the coil determines the induced emf. D) The factors affecting the induced emf in a coil include the rate of change of magnetic flux, number of turns in the coil, strength of the magnetic field, orientation of the coil, and resistance of the coil. Show Answer Correct Answer: D) The factors affecting the induced emf in a coil include the rate of change of magnetic flux, number of turns in the coil, strength of the magnetic field, orientation of the coil, and resistance of the coil. 6. A circular loop of radius 2cm, is placed in a time varing magnetic field with rate of 2T/sec. Then induced electric field in this loop will be A) 0.4V. B) 0.04 V. C) 4 mV. D) 0.12 V. Show Answer Correct Answer: B) 0.04 V. 7. Which rule is used to determine the direction of current flow when a conductor is cut across the magnetic field line A) Fleming's left hand rule. B) Fleming's right hand rule. C) Right hand grips rule. D) Faraday's palm rule. Show Answer Correct Answer: B) Fleming's right hand rule. 8. If the magnet falls from a certain height through the opening of the closed coil, then the acceleration of the magnet ..... A) Is modular constant and equals free fall acceleration;. B) Modulus of steel and greater than free fall acceleration;. C) Modulus constant and less than free fall acceleration;. D) Changes in modulus and less than the acceleration of free fall. Show Answer Correct Answer: D) Changes in modulus and less than the acceleration of free fall. 9. A coil of resistance 400 ohm is placed in a magnetic field. If the magnetic flux linked with the coil varies with time (t) as $\phi=50t^2+4$ A) 0.1 A. B) 0.5 A. C) 5 A. D) 1.5 A. Show Answer Correct Answer: B) 0.5 A. 10. What is Lenz's Law? A) Induced current opposes the change that caused it. B) Induced current enhances the change that caused it. C) Induced current is always zero. D) Induced current is independent of magnetic fields. Show Answer Correct Answer: A) Induced current opposes the change that caused it. 11. Eddy currents can be used to heat localised tissues of the human body. This branch of medical therapy is called A) Hyperthermia. B) Diathermy. C) Inductothermy. D) None of these. Show Answer Correct Answer: C) Inductothermy. 12. The unit of magnetic flux is the A) Henry. B) Tesla. C) Faraday. D) Weber. Show Answer Correct Answer: D) Weber. 13. Self-induced EMF is sometimes also known as A) Induced EMF. B) Deduce EMF. C) Back EMF. D) Both a and b. Show Answer Correct Answer: C) Back EMF. 14. A wire carries a current of 2 A over a period of 30 seconds. What total charge moves through the wire in this time interval? A) 15 C. B) 60 C. C) 0.0666 C. D) 120 C. Show Answer Correct Answer: B) 60 C. 15. What happens to the direction of the potential difference when the direction of the wire movement changes? A) The direction of the potential difference remains the same. B) The potential difference disappears. C) The potential difference increases. D) The direction of the potential difference swaps. Show Answer Correct Answer: D) The direction of the potential difference swaps. 16. The principle of electromagnetic induction is used in which of the following devices? A) Electric heater. B) Electric fan. C) Induction cooker. D) Electric bulb. Show Answer Correct Answer: C) Induction cooker. 17. ..... Law says that the Induced current is proportional to the change of magnetic flux A) Lenz'. B) Faraday's. C) Ampere's. D) None of the above. Show Answer Correct Answer: B) Faraday's. 18. Will a transformer work with direct current (d.c.) or alternating current (a.c.)? A) A.c. only. B) D.c. only. C) Both a.c. and d.c. D) None of the above. Show Answer Correct Answer: A) A.c. only. 19. What is the direction of induced current when a magnet is moved towards a coil? A) The induced current flows in the same direction as the magnet's movement. B) The induced current flows in the opposite direction to the magnet's movement. C) The induced current flows in a direction that opposes the change in magnetic flux, according to Lenz's Law. D) The induced current does not flow at all when the magnet is moved. Show Answer Correct Answer: C) The induced current flows in a direction that opposes the change in magnetic flux, according to Lenz's Law. 20. The function of a mains transformer is to convert A) One direct voltage to another direct voltage of different magnitude. B) One alternating voltage to another alternating voltage of different magnitude. C) A high value alternating voltage to a low value direct voltage. D) A low value alternating voltage to a high value direct voltage. Show Answer Correct Answer: B) One alternating voltage to another alternating voltage of different magnitude. 21. What is Faraday's Law of Electromagnetic Induction? A) Faraday's Law states that magnetic fields are not related to induced EMF. B) A change in electric field induces an electromotive force (EMF) in a closed circuit. C) Electromagnetic Induction only occurs in open circuits. D) A change in magnetic field induces an electromotive force (EMF) in a closed circuit. Show Answer Correct Answer: D) A change in magnetic field induces an electromotive force (EMF) in a closed circuit. 22. A transformer designed to step-down 240 V mains voltage to a voltage of 6 V AC. Calculate the number of turns on the secondary coil, given that the primary coil has 2000 turns. A) 20 turns. B) 50 turns. C) 150 turns. D) 200 turns. Show Answer Correct Answer: B) 50 turns. 23. What is a generator? A) A device that converts mechanical energy into electrical energy using electromagnetic induction. B) A machine that stores electrical energy for later use. C) A tool used to measure electrical resistance. D) A system that generates heat energy from solar power. Show Answer Correct Answer: A) A device that converts mechanical energy into electrical energy using electromagnetic induction. 24. What factors affect the magnitude of induced EMF? A) Length of the wire in the loop. B) Rate of change of magnetic flux, strength of magnetic field, area of the loop, orientation of the loop. C) Temperature of the environment. D) Type of conductor used. Show Answer Correct Answer: B) Rate of change of magnetic flux, strength of magnetic field, area of the loop, orientation of the loop. 25. In Transformer Ratio of voltages is equal to ratio of ..... A) Number of iron sheets in core. B) Number of coil. C) Number of turns in coil. D) Number of electromagnetic. Show Answer Correct Answer: C) Number of turns in coil. ← 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 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 10Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 11 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books