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 6 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 6 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Observe:Check that Show loop data is on. Move the wire loop up, away from the magnet. If so, in which direction is the current moving, left or right? A) Down. B) Left. C) Right. D) Up. Show Answer Correct Answer: B) Left. 2. The inductance in a coil plays the same role as A) Force in mechanics. B) Momentum in mechanics. C) Inertia in mechanics. D) Energy in mechanics. Show Answer Correct Answer: C) Inertia in mechanics. 3. The SI units of induced emf is A) Volt. B) Ohm. C) Tesla. D) Henry. Show Answer Correct Answer: A) Volt. 4. A student investigates the output voltage induced across a coil of wire by a bar magnet. When will the induced voltage have the greatest value? A) The student slowly moves the bar magnet into the coil of wire. B) The student places the bar magnet at rest outside the coil of wire. C) The student quickly removes the bar magnet from the coil of wire. D) The student leaves the bar magnet stationary in the coil of wire. Show Answer Correct Answer: C) The student quickly removes the bar magnet from the coil of wire. 5. What type of current is produced by a battery? A) Direct. B) Magnetic. C) Induced. D) Alternating. Show Answer Correct Answer: A) Direct. 6. A short bar magnet allowed to fall along the axis of horizontal metallic ring. Starting from rest, the distance fallen by the magnet in one second may be:- A) 4.0 m. B) 5.0 m. C) 7.0 m. D) 6.0 m. Show Answer Correct Answer: A) 4.0 m. 7. Factors that affect the voltage generation in Faraday's experiment is A) Number of Coils. B) Changing Magnetic Field. C) Changing environment. D) Option (a) and (b). Show Answer Correct Answer: D) Option (a) and (b). 8. For electromagnetism, what does the right hand rule explain? A) A charged particle moving through a magnetic field experiences a force. B) The direction of a magnetic field near a current-carrying wire. C) The direction of a magnetic field through a current-carrying coil. D) All of these. Show Answer Correct Answer: D) All of these. 9. What is the relationship between the rate of change of magnetic flux and induced EMF? A) The induced EMF decreases as the rate of change of magnetic flux increases. B) The induced EMF is inversely proportional to the rate of change of magnetic flux. C) The induced EMF is independent of the rate of change of magnetic flux. D) The induced EMF is directly proportional to the rate of change of magnetic flux. Show Answer Correct Answer: D) The induced EMF is directly proportional to the rate of change of magnetic flux. 10. What does EMF stand for? A) Electromagnetic Field. B) Electromagnetic Frequency. C) Electronic Music Foundation. D) Electromotive Force. Show Answer Correct Answer: D) Electromotive Force. 11. What is the primary purpose of an AC generator? A) To increase voltage. B) To store electrical energy. C) To convert electrical energy into mechanical energy. D) To convert mechanical energy into electrical energy. Show Answer Correct Answer: D) To convert mechanical energy into electrical energy. 12. There are 3 ways to increase the e.m.f, except? A) Move the wire or coil more quickly relative to the magnet. B) Use a coil with more turn of wire. C) Use aluminium coil. D) Use a stronger magnet. Show Answer Correct Answer: C) Use aluminium coil. 13. Name the law which gives information about the polarity of induced EMF A) Biot savart law. B) Ampere law. C) Lenz law. D) Coulomb's law. Show Answer Correct Answer: C) Lenz law. 14. If the direction of motion is reversed, the direction of the current ..... A) Reverses. B) Stays the same. C) All the above. D) None of the above. Show Answer Correct Answer: A) Reverses. 15. What is the result of cutting a magnet in half? A) The magnet ceases to function. B) The magnet is split into a north and a south pole. C) Each piece will have its own north and south poles. D) None of the above. Show Answer Correct Answer: C) Each piece will have its own north and south poles. 16. A 100% efficient transformer converts a 240 V input voltage to a 12 V output voltage. The output power of the transformer can be a maximum of 20 W.The output is connected to two 0.30 A bulbs in parallel. One of the bulbs fails. How does the current in the primary coil change? A) It increases by 0.15 A. B) It remains unchanged. C) It decreases by 0.015 A. D) It decreases by 0.30 A. Show Answer Correct Answer: C) It decreases by 0.015 A. 17. For a coil having L = 2mH, current flow through it is I = tet then the time at which emf becomes zero:- A) 2 sec. B) 1 sec. C) 3 sec. D) 4 sec. Show Answer Correct Answer: A) 2 sec. 18. An a.c. generator contains a coil that rotates at a rate of 4500 revolutions per minute. What is the frequency of the alternating current? A) 1.25 Hz. B) 75 Hz. C) 150 Hz. D) 4500 Hz. Show Answer Correct Answer: B) 75 Hz. 19. What is the induced current produced by? A) Relative motion between conductor and magnetic field. B) Static magnetic fields. C) High temperatures. D) Constant electric fields. Show Answer Correct Answer: A) Relative motion between conductor and magnetic field. 20. Square coil of side 16 cm having 200 turns rotating in magnetic field of 0.05 T with peak EMF of 12 V will produce angular velocity of A) 48 rad s$^{-1}$. B) 49 rad s$^{-1}$. C) 42 rad s$^{-1}$. D) 47 rad s$^{-1}$. Show Answer Correct Answer: D) 47 rad s$^{-1}$. 21. A moving conductor coil produces an induced e.m.f. This is in accordance with: A) Ampere's law. B) Coulomb's law. C) Faraday's law. D) Lenz's law. Show Answer Correct Answer: C) Faraday's law. 22. Can you produce current in a wire with a magnet that is sitting still? A) Yes; having a magnet near a wire is enough to excite the electrons. B) No; the magnetic field has to be changing to excite the electrons. C) No; magnets cannot create electricity. D) None of the following. Show Answer Correct Answer: B) No; the magnetic field has to be changing to excite the electrons. 23. What will be the direction of the induced current in a generator when the direction of the motion is upwards while the magnetic flux is to the right? A) To the left. B) Towards. C) Upwards. D) Away. Show Answer Correct Answer: D) Away. 24. A magnet can move in a coil of wire to produce electricity in which system? A) D.C. motor. B) Motor. C) Generator. D) Magnet. Show Answer Correct Answer: C) Generator. 25. What is the relationship between the primary and secondary voltages in an ideal transformer? A) Vp/Vs = Np/Ns. B) Vp/Vs = Ns/Np. C) Vp/Vs = 0. D) Vp/Vs = 1. Show Answer Correct Answer: A) Vp/Vs = Np/Ns. 26. What type of current is most commonly produced by power stations in India? A) Steady current. B) Variable current. C) Direct current. D) Alternating current. Show Answer Correct Answer: D) Alternating current. 27. What is the phenomenon called when electric current is generated by varying magnetic fields? A) Self-induction. B) Electromagnetic induction. C) Electrolysis. D) Magnetic flux. Show Answer Correct Answer: B) Electromagnetic induction. 28. What happens to the induced voltage if the number of coils in a wire increases? A) The induced voltage decreases as the number of coils increases. B) The induced voltage increases but not in a predictable manner. C) The induced voltage doubles when the number of coils doubles. D) The induced voltage remains the same regardless of the number of coils. Show Answer Correct Answer: C) The induced voltage doubles when the number of coils doubles. 29. A transformer has 5500 turns on the primary coil and 500 turns on the secondary coil. The output of the secondary coil is 110 V a.c. and is connected to a heater. The transformer is 100% efficient. The heater produces a power of 132 W. What is the current in the primary coil? A) 0.11 A. B) 11 A. C) 0.12 A. D) 12 A. Show Answer Correct Answer: A) 0.11 A. 30. What will be the acceleration of the falling bar magnet which passes through the ring such that the ring is held horizontally and the bar magnet is dropped along the axis of the ring? A) It depends on the diameter of the ring and the length of the magnet. B) It is equal due to gravity. C) It is less than due to gravity. D) It is more than due to gravity. Show Answer Correct Answer: C) It is less than due to gravity. 31. In the context of electromagnetic induction, what does "emf" stand for? A) Electric magnetic field. B) Electromotive force. C) Electromagnetic field. D) Electromagnetic force. Show Answer Correct Answer: B) Electromotive force. 32. A coil is rotated in a magnetic field. What is the effect on the induced EMF if the speed of rotation is doubled? A) The EMF is doubled. B) The EMF is quadrupled. C) The EMF remains the same. D) The EMF is halved. Show Answer Correct Answer: A) The EMF is doubled. 33. Faraday's Law states that the induced emf is proportional to Hide answers A) The current. B) The cross sectional area of the coil. C) The rate of change in the flux of the coil. D) None of the above. Show Answer Correct Answer: C) The rate of change in the flux of the coil. 34. Which object(s) have electric fields? A) Electric Charges. B) Magnets. C) Both Electric Charges & Magnets. D) Electric fields do not exist. Show Answer Correct Answer: A) Electric Charges. 35. A rectangular loop of area 5 metre square has 50 turns and carries a current of 1A. it is held in a uniform magnetic field of 0.1 Tesla at an angle of 30 degree.calculate the torque experienced by the coil A) 12.8Nm. B) 12Nm. C) 12.5Nm. D) 13.5Nm. Show Answer Correct Answer: C) 12.5Nm. 36. You have two magnets. One is in your hand and the other is sitting on a table. You move the SOUTH pole of your magnet near the SOUTH pole of the magnet on the table. What happens? A) Nothing. B) They repel. C) They attract. D) A chemical reaction. Show Answer Correct Answer: B) They repel. 37. If you break a bar magnet in half, you can separate the north and south pole of the original magnet. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 38. Which of the following best describes a magnetic flux? A) A measurement of the total magnetic field which passes through a given area. B) The force between magnets. C) The space where magnetism can be experienced. D) Vector field that describes the magnetic influence in magnetic materials. Show Answer Correct Answer: A) A measurement of the total magnetic field which passes through a given area. 39. Name the phenomenon in which an EMF is induced in a coil due to the change of current in the same coil A) Mutual induction. B) Self induction. C) All the above. D) None of the above. Show Answer Correct Answer: B) Self induction. 40. How do you make an electromagnet stronger? A) Add a motor and/or lightbulbs. B) Add more light bulbs and/or wire coils. C) Add more wire coils and/or a switch. D) Add more wire coils and/or batteries. Show Answer Correct Answer: D) Add more wire coils and/or batteries. 41. What is the phase relationship between the primary and secondary currents in an ideal transformer? A) Out of phase. B) 90 degrees out of phase. C) 180 degrees out of phase. D) In phase. Show Answer Correct Answer: D) In phase. 42. State which material is suitable to be the core of a transformer! A) Plastic. B) Aluminium. C) Aluminium and iron. D) Iron only. Show Answer Correct Answer: D) Iron only. 43. A square of side 'a' metre lies in the YZ plane in a region, where the magnetic field is given by $B=B_o\left(3i+3j-4k\right)T$ $B_o$ A) $4B_oa^2\\Wb$. B) $-4B_oa^2\\Wb$. C) $3B_oa^2\\Wb$. D) $2B_oa^2\\Wb$. Show Answer Correct Answer: C) $3B_oa^2\\Wb$. 44. Which of the following features of a transformer does not enhance the efficiency of a transformer? A) Insulated wires. B) Laminated core. C) Core made from soft-iron. D) Metallic core. Show Answer Correct Answer: D) Metallic core. 45. What is the significance of the magnetic field in Faraday's Law? A) The magnetic field only affects static charges. B) The magnetic field has no relation to electromotive force. C) The magnetic field is crucial as it induces electromotive force (EMF) when it changes over time. D) The magnetic field is irrelevant in electrical circuits. Show Answer Correct Answer: C) The magnetic field is crucial as it induces electromotive force (EMF) when it changes over time. 46. Determine the EMF induced in a coil that has 1200 evenly spaced turns and a radius of 2.5 cm, when a magnet is brought near its end so that the magnetic field inside it is increased from 0 to 0.060 T in 20 ms. A) 7.06 V. B) 1.52 V. C) 0.0032 V. D) 9.86 V. Show Answer Correct Answer: A) 7.06 V. 47. Magnetic flux depends on ..... A) Area of the coil. B) Magnetic field strength. C) Angle between magnetic field and the coil. D) All the mentioned are correct. Show Answer Correct Answer: D) All the mentioned are correct. 48. Assertion (A):A copper sheet is placed in a magnetic field. If we pull it out of the field or push it into the field, we experience an opposing force. Reason (R):According to Lenz's law, eddy current produced in sheet opposes the motion of the sheet. A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true but R is NOT the correct explanation of A. C) A is true but R is false. D) A is false and R is also false. Show Answer Correct Answer: A) Both A and R are true and R is the correct explanation of A. 49. Write the vector form of biot savart law A) C. B) D. C) A. D) B. Show Answer Correct Answer: D) B. 50. What happens when a conductor cuts across lines of magnetic flux? A) Conductor becomes magnetic. B) Induced current in the conductor. C) Conductor heats up. D) No effect on the conductor. Show Answer Correct Answer: B) Induced current in the conductor. 51. Flux linked through following coils changes with respect to time then for which coil an e.m.f. is not induced:- A) Copper coils. B) Wood coil. C) Iron coil. D) None. Show Answer Correct Answer: B) Wood coil. 52. The polarity of induced emf is given by A) Ampere's circuital law. B) Biot-Savart law. C) Lenz's law. D) Fleming's right hand rule. Show Answer Correct Answer: C) Lenz's law. 53. Assertion (A):An aircraft flies along the meridian, the potential develops at the ends of its wings. Reason (R):Whenever there is change in the magnetic flux e.m.f. induces. A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true but R is NOT the correct explanation of A. C) A is true but R is false. D) A is false and R is also false. Show Answer Correct Answer: A) Both A and R are true and R is the correct explanation of A. 54. A device that transforms electrical energy to mechanical energy is a A) Motor. B) Transformer. C) Generator. D) Magnet. Show Answer Correct Answer: A) Motor. 55. Which device uses electromagnetic induction to convert mechanical energy into electrical energy? A) Battery. B) Generator. C) Electric motor. D) Transformer. Show Answer Correct Answer: B) Generator. 56. The initial voltage across a capacitor is 12V. What is its voltage after two time constants? A) 1.2V. B) 6V. C) 1.6V. D) 3.0V. Show Answer Correct Answer: C) 1.6V. 57. Sebuah bola lampu tertulis 220 VAC, 50 W. Tegangan rata-rata yang melalui bola lampu tersebut adalah ..... A) $\frac{220\sqrt{2}}{5\pi}$. B) $\frac{440\sqrt{2}}{\pi}$. C) $\frac{110}{2\pi}$. D) $\frac{240\sqrt{2}}{\pi}$. E) $\frac{220\sqrt{3}}{3\pi}$. Show Answer Correct Answer: B) $\frac{440\sqrt{2}}{\pi}$. 58. What must occur for a magnetic field to induce an electric current? A) The magnetic field must be really big. B) The magnetic field must be stable. C) The magnetic field must be changing. D) The magnetic field must be from a permanent magnet. Show Answer Correct Answer: C) The magnetic field must be changing. 59. A step-up transformer is used before electricity is transmitted by overhead cables.Which statement explains why the step-up transformer is used? A) It increases the voltage to reduce energy loss in the cables. B) It increases the voltage to increase the speed at which the electricity travels. C) It increases the current to reduce energy loss in the cables. D) It increases the current to increase the speed at which the electricity travels. Show Answer Correct Answer: A) It increases the voltage to reduce energy loss in the cables. 60. Which are comes under the energy losses in a transformer A) Copper loss. B) Hysteresis loss. C) Iron loss. D) All of the above. Show Answer Correct Answer: D) All of the above. ← 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 7Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 8Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 9 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books