This quiz works best with JavaScript enabled. Home > Cbse > Class 12 > Science > Physics Part I > Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction – Quiz 13 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 13 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Calculate the magnetic flux if the magnetic field strength is 2 T and the area is 4 m$^{2}$ . A) 4 Wb. B) 6 Wb. C) 8 Wb. D) 10 Wb. Show Answer Correct Answer: C) 8 Wb. 2. Why there is no induced e.m.f or induced current if the straight wire moved parallel to the magnetic field? A) Weaker fields. B) Fields are stationary. C) Fields are not cut by the wire. D) Fields not touch the wire. Show Answer Correct Answer: C) Fields are not cut by the wire. 3. What type of transformer is used to increase the voltage from power stations. A) Step-down transformer. B) Step-up transformer. C) All the above. D) None of the above. Show Answer Correct Answer: B) Step-up transformer. 4. A loop of area 0.45 m$^{2}$ is in a uniform 0.03 T magnetic field. If the flux through the loop is 1.1 x 10$^{-2}$ Wb, what angle does the plane of the loop make with the magnetic field? A) 25 degrees. B) 55 degrees. C) 35 degrees. D) 90 degrees. E) 65 degrees. Show Answer Correct Answer: B) 55 degrees. 5. What is the cause of induced electric current in a secondary coil? A) Change in temperature. B) Change in voltage. C) Change in magnetic field lines. D) Change in resistance. Show Answer Correct Answer: C) Change in magnetic field lines. 6. Lenz's law obey ..... A) Second's newton law of motion. B) Principle of conservation of energy. C) Total conservation of momentum. D) None of the above. Show Answer Correct Answer: B) Principle of conservation of energy. 7. What happens when a wire cuts through magnetic field lines? A) It breaks. B) A voltage is induced. C) It generates heat. D) It becomes magnetic. Show Answer Correct Answer: B) A voltage is induced. 8. The voltage across the input terminals of a transformer is 110 V. The primary coil has 50 turns and the secondary coil has 120 turns. The output voltage of the transformer is A) 46 V. B) 55 V. C) 264 V. D) 180 V. Show Answer Correct Answer: C) 264 V. 9. Transformer works on which of the following principle A) Fleming's Law. B) Lenz's Law. C) Faraday's Law of Electromagenetic Induction. D) Ampere's Law. Show Answer Correct Answer: C) Faraday's Law of Electromagenetic Induction. 10. According to Lenz's law the direction of an induced current in a conductor will be that which tends to produce which of the following effects? A) Produce a greater heating effect. B) Oppose the effect which produces it. C) Enhance the effect which produces it. D) Produce the greatest voltage. Show Answer Correct Answer: B) Oppose the effect which produces it. 11. What happens when you move a bar magnet in and out of a coil of copper wire? A) It would make the copper wire produce a magnetic field. B) Electric current would be produced in the copper wire. C) Electric current would be produced in the magnet. D) The magnet would do nothing to the coil of wire. Show Answer Correct Answer: B) Electric current would be produced in the copper wire. 12. What happens if the wire remains still and the magnets move instead? A) The magnetic field collapses. B) The potential difference decreases. C) A potential difference is still induced. D) No potential difference is induced. Show Answer Correct Answer: C) A potential difference is still induced. 13. What is the effect of moving a magnet quickly in and out of a coil? A) It decreases the rate of change of magnetic flux, resulting in a lower induced voltage. B) It has no effect on the magnetic flux or induced voltage. C) It increases the rate of change of magnetic flux, resulting in a higher induced voltage. D) It reverses the direction of the magnetic field in the coil. Show Answer Correct Answer: C) It increases the rate of change of magnetic flux, resulting in a higher induced voltage. 14. In a transformer, the input power is ..... the output power. A) Less than. B) Equal to. C) Greater than. D) None of the above. Show Answer Correct Answer: B) Equal to. 15. Faraday's law relates to which of the following? A) Electric current and flux. B) Magnetic field and current. C) Voltage, current, and flux. D) Voltage and magnetic flux. E) None of these. Show Answer Correct Answer: D) Voltage and magnetic flux. 16. In which direction does the induced current flow in a circuit according to Lenz's Law? A) Opposite direction of the change in magnetic field. B) Same direction of the change in magnetic field. C) Random direction. D) No direction. Show Answer Correct Answer: A) Opposite direction of the change in magnetic field. 17. Which of the following gives the direction of the induced e.m.f.? A) Ampere. B) Lenz's law. C) Biot-Savart's law. D) Faraday's law. Show Answer Correct Answer: B) Lenz's law. 18. A transformer is used to step up and alternating EMF of 200 volt to 440 volt.if the primary coil has 1000 turns.calculate the number of turns in the secondary coil A) 2200. B) 2232. C) 2220. D) 2230. Show Answer Correct Answer: A) 2200. 19. What is the purpose of the earth wire in a domestic circuit? A) To regulate current flow. B) To increase resistance. C) To provide insulation. D) To prevent short-circuiting. Show Answer Correct Answer: D) To prevent short-circuiting. 20. Magnetic flux o(in Weber) linked with a closed circuit of resistance 10 ohm varies with time t(in seconds) as = 5t-4t + 1. The induced emf in the circuit at t = 0.2 sec. is A) 2.0 V. B) 0.4 V. C) -0.4 V. D) -2.0 V. Show Answer Correct Answer: A) 2.0 V. 21. To attract means ..... A) A force created by magnets that pulls some metals. B) The part of the magnet where the force is the strongest. C) To Pull towards. D) An object able to pull some metals towards itself. Show Answer Correct Answer: C) To Pull towards. 22. Magnetic flux is defined as A) The product of magnetic field strength and area. B) The scalar product of magnetic flux density and the area vector. C) The vector product of magnetic field and area. D) The product of magnetic field and current. Show Answer Correct Answer: B) The scalar product of magnetic flux density and the area vector. 23. A magnet is moved towards a coil (i) quickly (ii) slowly. The induced potential difference A) More in (i) than in (ii) case. B) More in (ii) than in (i) case. C) Same in both. D) Can't say. Show Answer Correct Answer: A) More in (i) than in (ii) case. 24. Which of the following scientists discovered that a changing magnetic field is required to induce an electric current? A) Einstein. B) Maxwell. C) Lenz. D) Faraday. Show Answer Correct Answer: D) Faraday. 25. If velocity of a conductor moving through a magnetic field B is made zero, then motional emf is: A) $-Blv$. B) $-\frac{Bl}{v}$. C) Zero. D) $-\frac{v}{Bl}$. Show Answer Correct Answer: C) Zero. 26. Below are the factors affecting the magnitude of induced e.m.f except ..... A) Increases the speed of relative motion. B) Increases the number of turns of the solenoid. C) Decreases the strength of magnetic field. D) None of the above. Show Answer Correct Answer: C) Decreases the strength of magnetic field. 27. Consider an inductor whose linear dimensions are tripled and the total number of turns per unit length is kept constant, what happens to the self-inductance? A) 27 times. B) 3 times. C) 9 times. D) 13 times. Show Answer Correct Answer: B) 3 times. 28. If the speed of a moving magnet through a coil is doubled, what happens to the induced voltage? A) It is quadrupled. B) It remains the same. C) It is doubled. D) It is halved. Show Answer Correct Answer: C) It is doubled. 29. The process of creating a current in a circuit by changing a magnetic field A) Electric generator. B) Magnet. C) Electric motor. D) Electromagnetic induction. Show Answer Correct Answer: D) Electromagnetic induction. 30. The d.c generator and a.c generator make use of electromagnetic induction to produce ..... A) Force. B) Energy. C) Power. D) Electricity. Show Answer Correct Answer: D) Electricity. 31. How does mutual induction occur between two coils? A) Mutual induction happens when a static magnetic field is applied to one coil. B) Mutual induction requires physical contact between the two coils. C) Mutual induction occurs only when both coils are connected to the same power source. D) Mutual induction occurs when a changing current in one coil induces an EMF in a nearby coil due to the changing magnetic field. Show Answer Correct Answer: D) Mutual induction occurs when a changing current in one coil induces an EMF in a nearby coil due to the changing magnetic field. 32. A ..... means of insulated copper wire wound closely in the form of a helix A) Conductor. B) Solenoid. C) Toroidal solenoid. D) Cyclotron. Show Answer Correct Answer: B) Solenoid. 33. What is the effective voltage of an AC generator with a peak voltage of 200 V? A) 100 V. B) 282 V. C) 200 V. D) 141 V. Show Answer Correct Answer: D) 141 V. 34. A(n) ..... electric current will create a changing magnetic field. A) Direct. B) Stable. C) Existing. D) Alternating. Show Answer Correct Answer: D) Alternating. 35. Faraday demonstrated that an electric current can be created by ..... A) Hooking a wire up to a battery. B) Moving a magnet near a wire. C) Running a generator. D) Having a magnet near by. Show Answer Correct Answer: B) Moving a magnet near a wire. 36. Which item does NOT use an electromagnet. A) A Ferris wheel. B) A doorbell. C) A galvonometer. D) A handheld compass. Show Answer Correct Answer: D) A handheld compass. 37. Calculate potential difference in the secondary coil based on the information given below.Vp = 240 VNp = 20Ns = 125Vs? A) 1000. B) 1500. C) 500. D) 2000. Show Answer Correct Answer: B) 1500. 38. A current-carrying conductor can induce current to another conductor. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 39. Explain Flemming's Right Hand Rule and its application. A) Fleming's Right Hand Rule is applied in physics to determine the direction of the force on a current-carrying conductor in a magnetic field. B) Fleming's Right Hand Rule is used to determine the speed of light in a vacuum. C) Fleming's Right Hand Rule is used to measure the temperature of a substance. D) Fleming's Right Hand Rule is used to calculate the resistance of a circuit. Show Answer Correct Answer: A) Fleming's Right Hand Rule is applied in physics to determine the direction of the force on a current-carrying conductor in a magnetic field. 40. Describe the basic principle of a transformer. A) A transformer operates based on the principle of chemical reactions. B) A transformer operates based on the principle of gravitational force. C) A transformer operates based on the principle of electromagnetic induction. D) A transformer operates based on the principle of nuclear fusion. Show Answer Correct Answer: C) A transformer operates based on the principle of electromagnetic induction. 41. In 1831 who discovered electromagnetic induction? A) Thomas Edison. B) Nikola Tesla. C) Michael Faraday. D) None of the above. Show Answer Correct Answer: C) Michael Faraday. 42. It is the measurement of the total magnetic field which passes through a given area. A) Electromotive Flux. B) Electromagnetic Flux. C) Electric Flux. D) Magnetic Flux. Show Answer Correct Answer: D) Magnetic Flux. 43. Which metal is used for the core of a transformer? A) Steel. B) Copper. C) Aluminium. D) Soft iron. Show Answer Correct Answer: D) Soft iron. 44. In an AC generator, the contacts are made from a soft but highly conductive material, usually carbon, and are called ..... A) Slip Rings. B) Brushes. C) Armatures. D) Coils. Show Answer Correct Answer: B) Brushes. 45. As electrons move, they make A) Electromagnetism. B) Magneticfields. C) Ferromagnetism. D) Auroras. Show Answer Correct Answer: B) Magneticfields. 46. Explain the concept of self-induction. A) Self-induction is the process of a coil storing energy in a magnetic field without any current. B) Self-induction is the process by which a changing current in a coil induces an electromotive force in itself. C) Self-induction occurs when a coil generates heat due to resistance. D) Self-induction refers to the ability of a coil to repel magnetic fields from other coils. Show Answer Correct Answer: B) Self-induction is the process by which a changing current in a coil induces an electromotive force in itself. 47. Explain the concept of eddy currents. A) Eddy currents are induced electric currents that flow in loops within conductors due to changing magnetic fields. B) Eddy currents are always harmful and cause overheating in all materials. C) Eddy currents are a type of fluid flow in liquids. D) Eddy currents are static charges that build up on the surface of conductors. Show Answer Correct Answer: A) Eddy currents are induced electric currents that flow in loops within conductors due to changing magnetic fields. 48. Which quantity is increased in a step-down transformer?(a) (b) Voltage (c) (d) A) Current. B) Frequency. C) Voltage. D) Power. Show Answer Correct Answer: A) Current. 49. Ratio of currents in transformer is equal to ratio of ..... A) Inverse ratio of number of turns. B) Number of coil. C) Number of electromagnetic. D) Number of iron sheets in core. Show Answer Correct Answer: A) Inverse ratio of number of turns. 50. You hold a flat, square loop of wire in a uniform magnetic field that is pointing from left to right. To make the magnetic flux through the loop equal to ZERO, how must you orient the loop? A) It is impossible for the flux to be zero unless the magnetic field is zero. B) Hold it "face-on" to the field, like a window facing the wind. C) Hold it "edge-on" to the field, like a knife-edge cutting the wind. D) Hold it at a 45-degree angle to the field. Show Answer Correct Answer: C) Hold it "edge-on" to the field, like a knife-edge cutting the wind. 51. The north pole of a bar magnet is rapidly introduced into a solenoid at one end (say A). Which of the following statements correctly depicts the phenomenon taking place? A) No induced emf is developed. B) The end A of the solenoid acquires positive potential. C) The end A of the solenoid behaves like a north pole. D) The end A of the solenoid behaves like a south pole. Show Answer Correct Answer: C) The end A of the solenoid behaves like a north pole. 52. How can you increase the EMF induced in a wire? A) By using a thinner wire. B) By painting the wire. C) By using a longer wire. D) By using more coils of wire. Show Answer Correct Answer: D) By using more coils of wire. 53. Which of the following must change if there is to be an induced emf? A) The position of the loop in the magnetic field. B) The magnetic flux. C) The resistance in the loop. D) The induced current. Show Answer Correct Answer: B) The magnetic flux. 54. How does the electric field change as the magnet approaches the loop? A) The electric field increases. B) The electric field decreases. C) The electric field fluctuates. D) The electric field remains constant. Show Answer Correct Answer: A) The electric field increases. 55. Based on the observations you have made, what is Faraday's law? A) Faraday's law states that electric current is the result of a magnetic field. B) Faraday's law states that electric fields are created by magnetic charges. C) Faraday's law states that magnetic fields are created by electric charges. D) Faraday's law states that a change in magnetic field within a closed loop induces an electromotive force. Show Answer Correct Answer: D) Faraday's law states that a change in magnetic field within a closed loop induces an electromotive force. 56. What would happen if you broke a bar magnet into 8 pieces? A) You would have 8 half magnets. B) You would have 4 complete magnets. C) They wouldn't be magnets anymore. D) You would have 8 complete magnets. Show Answer Correct Answer: D) You would have 8 complete magnets. 57. A metallic wire having the length of 2 metre and weight of 4 x10-3 newton is found to remain at rest in a uniform and transverse magnetic field of 2x10-4 Tesla the current flowing through the wires A) 1A. B) 2A. C) 5A. D) 10A. Show Answer Correct Answer: D) 10A. 58. What is the unit of inductance and how is it calculated? A) Henry (H). B) Farad (F). C) Ohm ($\Omega$). D) Joule (J). Show Answer Correct Answer: A) Henry (H). 59. In general, how do the current and electric field relate to the change in magnetic flux? A) They are unrelated. B) They are directly proportional. C) They are related through Faraday's law of induction. D) They are inversely proportional. Show Answer Correct Answer: C) They are related through Faraday's law of induction. 60. Whenever there is a relative motion between a coil and a magnet, the magnitude of induced emf set up in the coil does not depend upon the A) Relative speed between coil and magnet. B) Magnetic moment of coil. C) Resistance of coil. D) Number of turns in the coil. Show Answer Correct Answer: C) Resistance of coil. ← PreviousNext →Related QuizzesScience QuizzesClass 12 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 8 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books