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 7 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 7 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. How were we able to turn the electromagnet off? A) Hooking the wire up to the battery/. B) Moving the battery further away from metal objects. C) Disconnecting the circuit to stop current flow. D) None of the above. Show Answer Correct Answer: C) Disconnecting the circuit to stop current flow. 2. Regenerative braking can be used to achieve the following except ..... A) Slow down a roller coaster cart. B) Slow down a car. C) Slow down a train. D) Stop a train. Show Answer Correct Answer: D) Stop a train. 3. A device that converts electrical energy into kinetic energy A) Electric motor. B) Electromagnet. C) Electromagnetism. D) Electromagnetic induction. Show Answer Correct Answer: A) Electric motor. 4. Faraday's law of electromagnetic induction is based on the relationship between ..... and ..... A) Velocity and acceleration. B) Magnetic field and electric current. C) Temperature and pressure. D) Gravity and friction. Show Answer Correct Answer: B) Magnetic field and electric current. 5. What is the effect of increasing the number of turns on a solenoid? A) Has no effect on the induced emf. B) Reverses the direction of induced emf. C) Decreases the induced emf. D) Increases the induced emf. Show Answer Correct Answer: D) Increases the induced emf. 6. Lenz's law is a consequence of A) The law of conservation of momentum. B) Newton's second law of motion. C) The law of conservation of energy. D) The first law of thermodynamics. Show Answer Correct Answer: C) The law of conservation of energy. 7. A rectangular loop and a circular loop are moving out of a uniform magnetic field region. In which loop do you expect the induced emf to be constant A) Circular loop. B) Rectangular loop. C) Both (a) and (b). D) Neither (a) nor (b). Show Answer Correct Answer: B) Rectangular loop. 8. What is the function of a step up transformer? A) Increase the resistance through a wire. B) Increase the output current. C) Increase the output voltage. D) Increase the input voltage. Show Answer Correct Answer: C) Increase the output voltage. 9. In a generator, mechanical energy is converted into which type of energy? A) Nuclear energy. B) Thermal energy. C) Solar energy. D) Electrical energy. E) Mechanical energy. Show Answer Correct Answer: D) Electrical energy. 10. A magnet is cut into two, what poles are produced with the two magnets? A) Two positive; two negative. B) One positive; three negative. C) Either four positive or negative. D) Three positive; one negative. Show Answer Correct Answer: A) Two positive; two negative. 11. What is the purpose of the short circuit test in determining the equivalent circuit parameters of a transformer? A) To measure the impedance. B) To measure the core losses. C) To measure the leakage flux. D) To measure the copper losses. Show Answer Correct Answer: A) To measure the impedance. 12. A magnet is moved towards a coil at a constant speed. What happens to the magnetic flux through the coil? A) It remains constant. B) It becomes zero. C) It increases. D) It decreases. Show Answer Correct Answer: C) It increases. 13. Which field can accelerate an electron, but never change its speed? A) Electric field. B) Magnetic field. C) Both of these. D) Neither of these. Show Answer Correct Answer: B) Magnetic field. 14. Which of the following can be done to increase the induced current in the conductor? A) Using a larger magnet. B) Moving the magnet north pole first instead of the south pole. C) Moving conductor instead of the magnet. D) Using a coil instead of a single ring of wire. Show Answer Correct Answer: D) Using a coil instead of a single ring of wire. 15. Electrical energy is usually transmitted using alternating high voltages. Which of the following statement is incorrect? A) Alternating voltage means that voltage is easy to change. B) High voltage means less power loss during transmission, so more efficient. C) The voltage is step up before transmission and step down before reaching the home. D) The frequency of the a.c. is changed in stages before reaching the home at 50 Hz. Show Answer Correct Answer: D) The frequency of the a.c. is changed in stages before reaching the home at 50 Hz. 16. Which of the following will generate a current in a loop? A) A gravitational force. B) A moving magnet. C) Friction. D) A magnet. Show Answer Correct Answer: B) A moving magnet. 17. How does the direction of the current in the loop compare to the electric field? A) The current is perpendicular to the electric field. B) The current is in the same direction as the electric field. C) The current direction is independent of the electric field. D) The current is in the opposite direction to the electric field. Show Answer Correct Answer: D) The current is in the opposite direction to the electric field. 18. The EMF induced in a conductor is proportional to the rate at which magnetic field lines are cut by the conductor?The law above is? A) Lenz's law. B) Kirchoff's law. C) Faraday's law. D) None of the above. Show Answer Correct Answer: C) Faraday's law. 19. What does an electric generator do? A) Increases voltage levels. B) Stores electrical energy. C) Converts mechanical energy to electrical energy. D) Converts electrical energy to mechanical energy. Show Answer Correct Answer: C) Converts mechanical energy to electrical energy. 20. The induced current generated by a dynamo is affected by the following except A) Speed of rotation. B) Cross-sectional area of coil. C) Number of turns of coil. D) Magnetic field strength. E) Electric field strength. Show Answer Correct Answer: E) Electric field strength. 21. Which one of the following graph in following figures represents the variation of reactance x of a capacitor with frequency f of an AC supply. A) C. B) D. C) A. D) B. Show Answer Correct Answer: B) D. 22. What is the role of a transformer? A) A device that converts electrical energy into mechanical energy. B) A device that transfers electrical energy between two or more circuits through electromagnetic induction, typically used to increase or decrease voltage. C) A device that stores electrical energy for later use. D) A device that measures electrical current in a circuit. Show Answer Correct Answer: B) A device that transfers electrical energy between two or more circuits through electromagnetic induction, typically used to increase or decrease voltage. 23. What is the physics principle of a generator? A) Motor effect. B) Hall effect. C) Electromagnetic induction. D) Photoelectric effect. Show Answer Correct Answer: C) Electromagnetic induction. 24. A loop of wire is placed in a magnetic field that is increasing in strength. What happens to the induced current in the loop? A) It flows counterclockwise. B) It flows into the page. C) It flows clockwise. D) It remains zero. Show Answer Correct Answer: A) It flows counterclockwise. 25. What is the value of power factor in a series LCR circuit at resonance A) Zero. B) One. C) Minus one. D) None. Show Answer Correct Answer: A) Zero. 26. What is the voltage from an alternator half a turn/rotation after maximum positive output? A) Maximum Positive Output again. B) Maximun Negative output. C) Minimum Negative Output. D) Zero. Show Answer Correct Answer: B) Maximun Negative output. 27. What might happen if transformers didn't exist? A) The electricity in your house might have an extremely high voltage. B) Electricity could not be distributed through power lines to people's homes. C) Electricity could not be created at power plants. D) The direction of the electric current in your home might switch back and forth. Show Answer Correct Answer: A) The electricity in your house might have an extremely high voltage. 28. What is the purpose of the equivalent circuit of a transformer? A) To complicate the transformer operation. B) To simplify the transformer operation. C) To increase the losses in the transformer. D) To decrease the efficiency of the transformer. Show Answer Correct Answer: B) To simplify the transformer operation. 29. Two similar circular loops carry equal currents in the same direction. On moving the coils further apart, the electric current will A) Remain unaltered. B) Increases in one and decreases in the second. C) Increase in both. D) Decrease in both. Show Answer Correct Answer: C) Increase in both. 30. If we move a bar magnet back and forth inside a current containing iron coil, what would you expect to happen? A) The needle on galvanometer slides to the right edge (highest measurement). B) Nothing will happen. C) The needle on galvanometer slides to right and left as the magnet movement. D) The needle on voltmeter slides to the left edge. Show Answer Correct Answer: C) The needle on galvanometer slides to right and left as the magnet movement. 31. What is the effect of inserting an iron rod into a coil during electromagnetic induction? A) It increases the induced current. B) It has no effect. C) It decreases the induced current. D) It reverses the current direction. Show Answer Correct Answer: A) It increases the induced current. 32. It's the product of the magnetic flux density and the area normal to the lines of flux. A) Magnetic Flux Linkage. B) Magnetic Flux Density. C) Magnetic Flux. D) Magnetic Field. Show Answer Correct Answer: C) Magnetic Flux. 33. What is the basic idea behind electromagnetic induction? A) When a wire moves through magnetic field lines, it generates electricity. B) When a wire moves through electric field lines, it generates magnetism. C) When a wire moves through light waves, it generates electricity. D) When a wire moves through sound waves, it generates electricity. Show Answer Correct Answer: A) When a wire moves through magnetic field lines, it generates electricity. 34. The magnitude of the ..... of the charged particle depends on the strength of the magnetic field and the velocity of the particle. A) Force. B) Direction. C) Speed. D) Acceleration. Show Answer Correct Answer: D) Acceleration. 35. Which among the choices is NOT a factor that affects the magnitude of an electromotive force? A) Area of the coil. B) Orientation of the poles. C) Number of turns in the coil. D) Magnetic strength of the core. Show Answer Correct Answer: B) Orientation of the poles. 36. What is the effect of moving a conductor through a magnetic field? A) It has no effect. B) It induces a current. C) It increases resistance. D) It stops the current. Show Answer Correct Answer: B) It induces a current. 37. A simple electric generator induces an electromotive force (e.m.f.). Which modification would increase the induced e.m.f.? A) Reduce the strength of the magnetic field around the coil. B) Increase the distance between the magnetic poles. C) Increase the number of turns in the coil of the generator. D) Reverse the direction of the magnetic field. Show Answer Correct Answer: C) Increase the number of turns in the coil of the generator. 38. A step-up transformer increases A) Power. B) Energy. C) Neither. D) Both. Show Answer Correct Answer: A) Power. 39. What is the relationship between magnetic field strength and induced voltage? A) The induced voltage is independent of the magnetic field strength. B) The induced voltage is inversely proportional to the magnetic field strength. C) The induced voltage is directly proportional to the rate of change of the magnetic field strength. D) The induced voltage is proportional to the square of the magnetic field strength. Show Answer Correct Answer: C) The induced voltage is directly proportional to the rate of change of the magnetic field strength. 40. Which electrical device uses the turning effect produced by a current-carrying coil in a magnetic field? A) A.c. generator. B) D.c. motor. C) Relay. D) Transformer. Show Answer Correct Answer: B) D.c. motor. 41. Which device relies upon the magnetic effect of an electric current? A) Variable resistor. B) Thermistor. C) Relay. D) Fuse. Show Answer Correct Answer: C) Relay. 42. Why is soft iron prefer to Steel in making the core of a transformer A) Energy loss per unit volume due to hysteresis is low. B) Energy loss per unit volume due to hysteresis is high. C) Energy loss per unit volume due to hysteresis normal. D) None of the above. Show Answer Correct Answer: A) Energy loss per unit volume due to hysteresis is low. 43. How does the frequency of AC affect its applications? A) The frequency of AC has no impact on its applications. B) Higher frequency always leads to better performance in all devices. C) AC frequency is only relevant for power generation, not for consumer electronics. D) The frequency of AC affects its applications by influencing efficiency, suitability for devices, and performance characteristics. Show Answer Correct Answer: D) The frequency of AC affects its applications by influencing efficiency, suitability for devices, and performance characteristics. 44. The unit of electromotive force is ..... A) Tesla. B) Newton. C) Electron . volt. D) Volt. Show Answer Correct Answer: D) Volt. 45. If the angle between the magnetic field and the area vector is 90$^\circ$, the magnetic flux is A) Equal to the magnetic field strength. B) Maximum. C) Zero. D) Minimum. Show Answer Correct Answer: C) Zero. 46. What does Faraday's Law state about electromagnetic induction? A) Electromagnetic induction occurs only in superconductors. B) Faraday's Law states that a change in magnetic flux induces an electromotive force in a circuit. C) A constant magnetic field generates an electric current without any change. D) Faraday's Law states that electric current can create a magnetic field without any flux change. Show Answer Correct Answer: B) Faraday's Law states that a change in magnetic flux induces an electromotive force in a circuit. 47. Which rule is used to determine the direction of force on a conductor due to motor effect? A) Fleming's left-hand rule. B) Fleming's right-hand rule. C) Right hand grip rule. D) Left hand grip rule. Show Answer Correct Answer: A) Fleming's left-hand rule. 48. Electrical energy is transferred by transmission lines at high voltage. Which statement explains why a high voltage is used? A) The voltage is alternating. B) The transmission lines have a larger resistance. C) The transmission lines carry greater power. D) There is a smaller current in the transmission lines for the same power. Show Answer Correct Answer: D) There is a smaller current in the transmission lines for the same power. 49. What types of metals are attracted to a magnet? A) Steel. B) Iron. C) Nickel. D) All of the above are attracted to magnets. Show Answer Correct Answer: D) All of the above are attracted to magnets. 50. What happens to the magnetic field when the direction of the current in a wire is reversed? A) The magnetic field will increase in strength. B) The magnetic field will reverse direction as well. C) The magnetic field will remain unchanged. D) The magnetic field will decrease in strength. Show Answer Correct Answer: B) The magnetic field will reverse direction as well. 51. The core of a transformer is made of iron because ..... A) It is strong. B) It is a soft magnetic material. C) It is a hard magnetic material. D) It has a high melting point. E) It conducts electricity. Show Answer Correct Answer: B) It is a soft magnetic material. 52. A current in a solenoid produces a uniform magnetic field inside the solenoid. The magnetic field direction is due east. Which changes will produce a stronger magnetic field with a direction due west? A) Use a smaller current and turn the solenoid through 180$^\circ$. B) Use a smaller current and reverse the current. C) Use a larger current and turn the solenoid through 90$^\circ$. D) Use a larger current and reverse the current. Show Answer Correct Answer: D) Use a larger current and reverse the current. 53. A transformer has 2.000 turns of the primary winding and 200 V the primary voltage. Determine the secondary winding if the secondary voltage 150 V. A) 1000 turns. B) 2000 turns. C) 500 turns. D) 1500 turns. Show Answer Correct Answer: D) 1500 turns. 54. The unit of inductance is: A) Volt. B) Ampere. C) Henry. D) Farad. Show Answer Correct Answer: C) Henry. 55. A motor converts electrical current into:mechanical energy/force A) Electric energy. B) Mechanical energy/force. C) Chemical energy. D) Mechanical life. Show Answer Correct Answer: B) Mechanical energy/force. 56. An aircraft wingspan is 25m long. It passes through a magnetic field of strength 1.5T at a speed of 50m/s. What is the e.m.f induced on the wings to 2 significant figures? A) 1900V. B) 1200V. C) 1800V. D) 1500V. Show Answer Correct Answer: A) 1900V. 57. What is the SI unit of magnetic flux linkage? A) Weber. B) Ampere. C) Volt. D) Tesla. Show Answer Correct Answer: A) Weber. 58. What is the symbol for Inductance? A) X$_{L}$. B) Z. C) I. D) L. Show Answer Correct Answer: D) L. 59. A flat coil consists of 20 turns each of area an area of 50 cm2, is positioned perpendicularly to a uniform magnetic field that increases its magnitude at a constant rate from 2.0 T to 6.0 T in 2.0 s. If the coil has a total resistance of 0.40 ohms, what is the magnitude of the induced current? A) 500 mA. B) 140 mA. C) 800 mA. D) 70 mA. Show Answer Correct Answer: A) 500 mA. 60. Two electromagnets contain the same types of magnets and wires. But the magnet in the first moves much faster than the second. Therefore: A) The currents in the two electromagnets run in opposite directions. B) The first electromagnet has a more powerful current than the second. C) The first electromagnet has a less powerful current than the second. D) The current in the first electromagnet moves faster than the current in the second electromagnet. Show Answer Correct Answer: B) The first electromagnet has a more powerful current than the second. ← 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 8Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 9 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books