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 9 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 9 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. The coil has 500 turns. When the current is changed to 2 A, the magnetic flux through each turn changes by 4 mWb. Determine the inductance of the coil. A) 0, 1 H. B) 2 H. C) 0, 2 H. D) 1 H. Show Answer Correct Answer: D) 1 H. 2. What is the primary factor that affects the amount of induced emf in a coil? A) The speed of the coil's rotation. B) The temperature of the coil. C) The color of the coil. D) The length of the coil. Show Answer Correct Answer: A) The speed of the coil's rotation. 3. Changing current in a coil produces emf in the same coil. this phenomenon is known as A) Mutual induction. B) Induced emf. C) Self induction. D) Induced current. Show Answer Correct Answer: C) Self induction. 4. A(n) ..... converts electric energy into mechanical energy . A) Electric transformer. B) Electric generator. C) Electric motor. D) Electromagnet. Show Answer Correct Answer: C) Electric motor. 5. Besarnya ggl induksi yang dihasilkan sebuah dinamo dipengaruhi oleh faktor-faktor berikut ini, kecuali ..... A) Kecepatan putaran kumparan. B) Jumlah lilitan kumparan. C) Luas penampang kumparan. D) Kuat medan magnet yang digunakan. E) Panjang kumparan. Show Answer Correct Answer: E) Panjang kumparan. 6. The electricity delivered to our homes from power stations is transmitted at high voltages and low currents because A) It is safer for engineers to repair the overhead cables. B) Electricity can travel faster along the cables. C) It reduces the resistance of the cables. D) It is cost effective in terms of energy lost. Show Answer Correct Answer: D) It is cost effective in terms of energy lost. 7. Write the equation for magnetic field B at a point A) A. B) B. C) All the above. D) None of the above. Show Answer Correct Answer: B) B. 8. What is mutual induction? A) Induction between two closely placed coils. B) Induction caused by a static charge. C) Induction in a single coil. D) Induction in a magnetic field only. Show Answer Correct Answer: A) Induction between two closely placed coils. 9. You are involved in after-hours conference calls with the US for the third time this week. You have already made alternative arrangements. Do you: A) Give what you think is a cast-iron reason for not taking part. B) Try saying no but end up taking part. C) Complain that it's the third time this week and say a definite "NO". D) Say 'no' firmly and say when you will have to leave for your other appointment. Show Answer Correct Answer: D) Say 'no' firmly and say when you will have to leave for your other appointment. 10. Which of the following would increase the EMF supplied by a generator? A) Decreasing the number of turns in the coil. B) Decreasing the strength of the magnetic field. C) Decreasing the time for one revolution. D) Decreasing the area of the coil. Show Answer Correct Answer: C) Decreasing the time for one revolution. 11. The symbol and units of self-inductance are A) C (Conductance). B) L (Henrys). C) C (Farads). D) F (Flux). Show Answer Correct Answer: B) L (Henrys). 12. Assertion (A):Self-inductance is called the inertia of electricity. Reason (R):Self-inductance is the phenomenon, according to which an opposing induced e.m.f. is produced in a coil as a result of change in current or magnetic flux linked with the coil. 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. 13. Alternating current is produced in most power stations. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 14. Inductor stores energy in the form of A) Electromagnetic field. B) Electric field. C) Magnetic field. D) None of the above. Show Answer Correct Answer: C) Magnetic field. 15. Which object(s) have magnetic fields? A) Electric Charges. B) Magnets. C) Both Electric Charges & Magnets. D) Magnetic fields do not exist. Show Answer Correct Answer: C) Both Electric Charges & Magnets. 16. How is the direction of induced current determined in electromagnetic induction? A) By Ohm's Law. B) By Faraday's Law. C) By Lenz's Law. D) By Newton's Law. Show Answer Correct Answer: C) By Lenz's Law. 17. What is the material used for construction of transformer core? A) Copper. B) Wood. C) Aluminium. D) Iron. Show Answer Correct Answer: D) Iron. 18. What is the flow of electricity? A) Electric circuit. B) Electric current. C) Electric eel. D) Electric motor. Show Answer Correct Answer: B) Electric current. 19. The magnitude of induced current is directly proportional to the rate of ..... linked with the coil A) Magnetic field. B) Change of magnetic field. C) Number of magnetic field lines. D) Change of number of magnetic field lines. Show Answer Correct Answer: D) Change of number of magnetic field lines. 20. A uniform magnetic field its intensity is 3x10$^{-3}$ T pass anarea of coil with 100 turns which makes 60 angle with the coil. What is the area of the coil if the magnetic flux is 0.15 Wb? A) 0.57 m$^{2}$. B) 1 m$^{2}$. C) 0 m$^{2}$. D) 0.5 m$^{2}$. Show Answer Correct Answer: B) 1 m$^{2}$. 21. An A.C. generator converts kinetic energy to A) Potential energy. B) Light energy. C) Thermal energy. D) Electric energy. Show Answer Correct Answer: D) Electric energy. 22. Which of the following best describes EMF? A) Can be thought of as the difference between two electrical states in an electric field. B) The potential difference generated by one or more cells or a changing magnetic field. C) Depends on the magnitude and resistance of the current. D) Force that causes an electric charge to flow. Show Answer Correct Answer: B) The potential difference generated by one or more cells or a changing magnetic field. 23. According to Faraday's first law of electromagnetic induction, what is induced when a conductor is placed in a varying magnetic field? A) Power. B) Voltage. C) Current. D) Resistance. Show Answer Correct Answer: C) Current. 24. What is the principle behind electromagnetic induction? A) Faraday's Law. B) Newton's Law. C) Ohm's Law. D) Coulomb's Law. Show Answer Correct Answer: A) Faraday's Law. 25. An electron of charge, e, enters a magnetic field at right angles. Which of the following equations can be used to determine the momentum of this electron? A) B/re. B) E/Br. C) Ber. D) RB/e. Show Answer Correct Answer: C) Ber. 26. A device that converts mechanical energy into electrical energy using electromagnetic induction is called a: A) Motor. B) Transformer. C) Battery. D) Generator. Show Answer Correct Answer: D) Generator. 27. What is the significance of the negative sign in Lenz's Law? A) The negative sign indicates the direction of the magnetic field. B) The negative sign is irrelevant to the behavior of magnetic fields. C) The negative sign represents the strength of the induced current. D) The negative sign signifies the opposition of induced current to the change in magnetic flux. Show Answer Correct Answer: D) The negative sign signifies the opposition of induced current to the change in magnetic flux. 28. Wire loop is rotated in magnetic field. The frequency of change of direction of the induced emf is A) Twice per revolution. B) Thrice per revolution. C) Once per revolution. D) Four times per revolution. Show Answer Correct Answer: A) Twice per revolution. 29. An electromagnetic induction setup can be made without using a galvanometer. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 30. Electromagnetic induction occurs in a coil when there is a change in A) Electric field in the coil. B) Magnetic field in the coil. C) Voltage in the coil. D) None of the above. Show Answer Correct Answer: B) Magnetic field in the coil. 31. What is the main method used for generating electricity? A) Thermal Induction. B) Chemical Induction. C) Electrostatic Induction. D) Electromagnetic Induction. Show Answer Correct Answer: D) Electromagnetic Induction. 32. A circular conducting loop is placed in a magnetic field perpendicular to the plane of the loop. As the magnetic field decreases at a rate of 0.040 T/s, an emf of 2.6 mV is induced in the loop. Find the radius of the loop. A) 0.02 m. B) 0.35 m. C) 2.1 m. D) 4.5 m. E) 0.14 m. Show Answer Correct Answer: E) 0.14 m. 33. In a transformer, if the primary coil has more turns than the secondary coil, what happens to the voltage? A) Triples. B) Increases. C) Doubles. D) Decreases. E) Remains the same. Show Answer Correct Answer: D) Decreases. 34. State Faraday's law of electromagnetic induction. A) The induced EMF in a circuit is directly proportional to the rate of change of magnetic flux through the circuit. B) The induced EMF is only present in closed circuits. C) The induced EMF is inversely proportional to the magnetic field strength. D) The induced EMF is constant regardless of magnetic flux changes. Show Answer Correct Answer: A) The induced EMF in a circuit is directly proportional to the rate of change of magnetic flux through the circuit. 35. A transformer has 48 turns on its primary coil. It has an input voltage of 88 V and output voltage of 264V. How many turn are on the secondary coil? A) 114. B) 144. C) 484. D) 6. Show Answer Correct Answer: B) 144. 36. A transformer with 240V AC input and 50V AC output, has 400 turns on its primary coil. Is it a step down or a step up transformer A) Step-up. B) Step-down. C) All the above. D) None of the above. Show Answer Correct Answer: B) Step-down. 37. When the voltage in the secondary coil decreases, it is called step-down transformer. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 38. A device such as dynamo used to generate alternating current? A) D.C generator. B) A.C generator. C) All the above. D) None of the above. Show Answer Correct Answer: B) A.C generator. 39. Unit for self induction A) Henry. B) Volt. C) Wb. D) T. Show Answer Correct Answer: A) Henry. 40. In Flemings Left hand rule what does the thumb point in the direction of? A) The direction of the magnetic field. B) The direction of the current. C) The direction of the force (movement). D) None of these. Show Answer Correct Answer: C) The direction of the force (movement). 41. Electromagnetic Induction IGCSE A) The change in magnetic field direction. B) The change in electric field strength. C) The change in electric current. D) The change in magnetic flux. Show Answer Correct Answer: D) The change in magnetic flux. 42. The Law of Conservation of Energy states that ..... A) Energy can be created when a new power source is introduced. B) Energy is destroyed when a circuit is broken. C) Energy can be created using a generator. D) Energy can neither be created nor destroyed. Show Answer Correct Answer: D) Energy can neither be created nor destroyed. 43. When the rate of change of current through a closed circuit is unity, then the induced e.m.f. produced in it is equal to A) Current. B) Coefficient of self induction or self inductance L. C) Electric field. D) Voltage. Show Answer Correct Answer: B) Coefficient of self induction or self inductance L. 44. An L-R circuit consists of an inductance of 8mH and a resistance of 42. The time constant of the circuit is A) 12ms. B) 32ms. C) 2ms. D) 500 s. Show Answer Correct Answer: C) 2ms. 45. Assertion (A):When two coils are wound on each other, the mutual induction between the coils is maximum. Reason (R):Mutual induction does not depend on the orientation of the coils. 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: C) A is true but R is false. 46. How is electromagnetic induction used in generators? A) By rotating a coil of wire within a magnetic field. B) By using a permanent magnet to generate electricity. C) By heating a wire to create an electric current. D) By passing a current through a coil of wire. Show Answer Correct Answer: A) By rotating a coil of wire within a magnetic field. 47. The pointer of a galvanometer needle whose terminals are connected to a solenoid coilwill be deflected if one withdraws the magnet quickly from the coil because ..... A) The number of the coil turns is very large. B) The coil intercepts the lines of the magnetic flux. C) The number of turns of the coil is suitable. D) The number of turns of the coil is small. Show Answer Correct Answer: B) The coil intercepts the lines of the magnetic flux. 48. An alternating current of frequency f is flowing through an ideal choke coil of self inductance L if V0 and I0 be the peak value of the voltage and the current. find the average power consumed by the choke coil A) One. B) Zero. C) Minus one. D) None. Show Answer Correct Answer: B) Zero. 49. A coil having self inductance of 0.7 and resistance of 165 ohm is connected to a AC source of 275 v 50 Hz calculate 1. Reactance of the coil 2. current flowing through the coil.3.Impendence of the coil A) .240ohm(2).285ohm(3).2A. B) .240ohm(2).275ohm(3).3A. C) .220ohm(2).275ohm(3).1A. D) .242ohm(2).285ohm(3).1A. Show Answer Correct Answer: C) .220ohm(2).275ohm(3).1A. 50. A 9 V battery is connected to three 30 $\Omega$ resistors in series. How much current (in amperes) flows through the battery? A) $0.1$. B) 0.1 Mathematical EquivalenceON. C) All the above. D) None of the above. Show Answer Correct Answer: A) $0.1$. 51. SI unit of Magnetic flux is A) Waber. B) Watt. C) Tesla. D) Weber. Show Answer Correct Answer: D) Weber. 52. What is the role of the magnetic field in electromagnetic induction? A) It opposes all electric currents. B) It generates heat. C) It induces current in a conductor. D) It has no role. Show Answer Correct Answer: C) It induces current in a conductor. 53. The SI unit of magnetic flux, causing the e.m.f. of one volt in a circuit of one turn when the flux is uniformly reduced to zero in one second. A) Tesla. B) Weber. C) Tesla turns. D) Weber turns. Show Answer Correct Answer: B) Weber. 54. What is the use of slip rings in a simple a.c. generator? A) To increase the rotational speed of the coil. B) To prevent the wire from entanglement. C) To change the direction of current flowing to the load in every half a turn. D) To ensure good contacts between the moving parts and the stationary parts. Show Answer Correct Answer: D) To ensure good contacts between the moving parts and the stationary parts. 55. What happens to the induced current if the speed of the moving magnet is increased? A) The current decreases. B) The current increases. C) The current reverses direction. D) The current remains the same. Show Answer Correct Answer: B) The current increases. 56. The direction of a magnetic field's lines always head towards the South pole. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 57. Derive an expression for the motional EMF induced across the ends of a conducting rod moving in a uniform perpendicular magnetic field A) E=Blx. B) E=Bla. C) E=Blq. D) E=Blv. Show Answer Correct Answer: D) E=Blv. 58. A solenoid bent in the form of a closed ring is called ..... A) Cyclotron. B) Solenoid. C) Toroidal solenoid. D) None. Show Answer Correct Answer: C) Toroidal solenoid. 59. What is inside a toy car that turns the wheels? A) Generator. B) Electric motor. C) Electromagnet. D) None of the above. Show Answer Correct Answer: B) Electric motor. 60. A resistor of resistance 100 ohms is connected in series with a 10mF capacitor. What is its half-life? A) 10s. B) 6.93s. C) 693s. D) 0.693s. Show Answer Correct Answer: D) 0.693s. ← 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