This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction – Quiz 15 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 15 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. 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) $2B_oa^2\\Wb$. B) $3B_oa^2\\Wb$. C) $4B_oa^2\\Wb$. D) $-4B_oa^2\\Wb$. Show Answer Correct Answer: B) $3B_oa^2\\Wb$. 2. 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. 3. What is the significance of the magnetic field in Faraday's Law? A) The magnetic field only affects static charges. B) The magnetic field is crucial as it induces electromotive force (EMF) when it changes over time. C) The magnetic field is irrelevant in electrical circuits. D) The magnetic field has no relation to electromotive force. Show Answer Correct Answer: B) The magnetic field is crucial as it induces electromotive force (EMF) when it changes over time. 4. 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) 0.0032 V. B) 1.52 V. C) 7.06 V. D) 9.86 V. Show Answer Correct Answer: C) 7.06 V. 5. 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. 6. 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. 7. Write the vector form of biot savart law A) A. B) B. C) C. D) D. Show Answer Correct Answer: B) B. 8. What happens when a conductor cuts across lines of magnetic flux? A) Conductor becomes magnetic. B) Conductor heats up. C) Induced current in the conductor. D) No effect on the conductor. Show Answer Correct Answer: C) Induced current in the conductor. 9. 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. 10. 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. 11. 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. 12. A device that transforms electrical energy to mechanical energy is a A) Generator. B) Motor. C) Transformer. D) Magnet. Show Answer Correct Answer: B) Motor. 13. Which device uses electromagnetic induction to convert mechanical energy into electrical energy? A) Electric motor. B) Transformer. C) Generator. D) Battery. Show Answer Correct Answer: C) Generator. 14. An e.m.f. is induced across a wire when it moves through opposite magnetic field between the poles of a magnet.Which electrical device operates because of this effect? A) A battery. B) A cathode ray tube. C) A simple motor. D) A generator. Show Answer Correct Answer: D) A generator. 15. The initial voltage across a capacitor is 12V. What is its voltage after two time constants? A) 1.2V. B) 1.6V. C) 3.0V. D) 6V. Show Answer Correct Answer: B) 1.6V. 16. Sebuah bola lampu tertulis 220 VAC, 50 W. Tegangan rata-rata yang melalui bola lampu tersebut adalah ..... A) $\frac{440\sqrt{2}}{\pi}$. B) $\frac{220\sqrt{3}}{3\pi}$. C) $\frac{110}{2\pi}$. D) $\frac{220\sqrt{2}}{5\pi}$. E) $\frac{240\sqrt{2}}{\pi}$. Show Answer Correct Answer: A) $\frac{440\sqrt{2}}{\pi}$. 17. 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. 18. 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 current to increase the speed at which the electricity travels. B) It increases the current to reduce energy loss in the cables. C) It increases the voltage to increase the speed at which the electricity travels. D) It increases the voltage to reduce energy loss in the cables. Show Answer Correct Answer: D) It increases the voltage to reduce energy loss in the cables. 19. 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. 20. 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. 21. Regenerative braking can be used to achieve the following except ..... A) Slow down a train. B) Slow down a car. C) Slow down a roller coaster cart. D) Stop a train. Show Answer Correct Answer: D) Stop a train. 22. A device that converts electrical energy into kinetic energy A) Electromagnet. B) Electromagnetic induction. C) Electric motor. D) Electromagnetism. Show Answer Correct Answer: C) Electric motor. 23. 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. 24. What is the effect of increasing the number of turns on a solenoid? A) Reverses the direction of induced emf. B) Decreases the induced emf. C) Increases the induced emf. D) Has no effect on the induced emf. Show Answer Correct Answer: C) Increases the induced emf. 25. Lenz's law is a consequence of A) The law of conservation of momentum. B) The law of conservation of energy. C) Newton's second law of motion. D) The first law of thermodynamics. Show Answer Correct Answer: B) The law of conservation of energy. ← 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 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 8Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 9Class 12 Physics (Part I) Chapter 6 Electromagnetic Induction Quiz 10 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books