CH-15 Electromagnetic Induction Leave a Comment / By abdulslambsn@gmail.com / October 6, 2025 Welcome To Your Quiz "CH-15 Electromagnetic Induction" Click on "Start Quiz" To Continue... 1. The induced current can be increased by: Replacing the loop by a coil Moving the loop faster Using the strong magnetic field All of the above None 2. The phenomenon by which an induced emf is produced in the conductor due to change of magnetic flux in it is called: Electromagnetism Electromagnetic induction Electric polarization All of the above None 3. In magnet- coil experiment, emf can be produced by: Motion of loop and magnet Keeping the magnet stationary and moving the coil Keeping the coil stationary and moving magnet All of the above None 4. A coil of constant area is placed in a constant magnetic field, and induced current is produced in the coil when: The coil is rotated The coil is stationary Both A and B None of these None 5. Faraday's law of electromagnetic induction has been used in the construction of: Electric generator Ammeter Galvanometer All of the above None 6. The rate of change of magnetic flux is directly proportional to induced emf is called: Lenz law Faraday's law Oersted law None of them None 7. The direction of induced current is always so as to oppose the change which causes the current, this is the statement of: Lenz' law Faraday's law Ampere's law Coulomb law None 8. When we study the phenomenon mutual induction between two coils, the primary coil consists of: A rheostat and battery A rheostat and galvanometer Galvanometer only None of these None 9. If the current in the coil itself is increased by rheostat, the emf induced will be: Opposite to that of battery In the same direction at that of battery Both A and B None of these None 10. A coil of wire is also called: Insulator Semi-conductor Inductor All of above None 11. Energy stored per unit volume inside a long solenoid is known as: Energy density Power density Energy Surface charge density None 12. The practical illustration of the phenomenon of mutual induction in: Transformer D.C. dynamo A.C generator None of these None 13. The phenomenon of producing emf in a coil due to the change of current in itself is called: Self induction Mutual induction Inductance Both A and B None 14. The self induction does not depend upon: Core material Weight of coil Number of turns of the coil Area of coil None 15. The ratio of the emf in the secondary coil to the rate of change of current in the primary coil is known as: Mutual induction Self induction Mutual inductance Both A and C None 16. A 50 mH coil carries a current of 2A. The energy stored in its magnetic field is: E = 005 J E = 10 J E = 0.1 J E = 50 J None 17. An electric motor converts: Mechanical energy into electrical energy Electrical energy into mechanical energy Magnetic energy into mechanical energy None of the above None 18. Alternating emf is produced by rotating a coil of wire in: Electric field Magnetic field Conservative field Gravitational field None 19. The only difference between construction of D.C generator and A.C generator is that of: Commutator Coil Carbon brushes Magnetic field None 20. Who invented commutator: William Black William Smith William Sturgoen Mosley None 21. Energy stored per unit volume inside the solenoid is called: Mass density Energy density Charge density Volume density None 22. For the use of an electric lamp of low voltage and A.C main of high voltage, we use the device called: Resistor Rheostat Transformer Solenoid None 23. A straight line conductor of length 0.4 m is moved with speed of 7 m/s perpendicular to the magnetic field 0.9 Wb/m². The induced emf across the conductor is: 1.26 volt 25.2 volt 2.52 volt 5.04 volt None 24. If the number of turn in a coil is increased metallic ring to 3 times then its initial number, then the magnetic flux is linked with is: Becomes one third of its initial value Remains unchanged Becomes nine times of its initial value Increased by three times None 25. When a current carrying conductor placed in an external magnetic field experience a force. The device whose working based on this principle is: Electric bell Electric motor Dynamo None of these None 26. To set up voltage the number of turns in the secondary should be: Less than the number of turns in the primary Greater than the number of turns in the primary Equal the number of turns in the primary Infinite None 27. The coil from which the power is delivered to the circuit is called: Primary coil Secondary coil Field coil None of these None 28. To improve the efficiency of a transformer: Insulation should be perfect Resistance of both should be least Core should be laminated All of above None 29. The turn ratio of setup transformer is the voltage ratio and current ratio respectively will be: 25,50 50,0.02 0.02,50 50 volt, 0.02 A None 30. Which one of the following materials is more suitable for making cores of Transformer? Soft iron Copper Nickel Aluminum None 31. A coil of 10 cm x 20 cm having 40 turns in making 18.00 rev/min in a magnetic field 0.5 wb/m². The peak value of induced emf is: 113 volt 226 volt 339 volt 452 volt None 32. A loop of wire is suspended between poles of magnet with its plane parallel to pole faces. What happens if A.C is used? Coil oscillate Coil rotate Coil remain at rest Both a and b None 33. The phenomenon in which changing current in one coil induces an e.m.f. in another coil is called: Mutual inductance Self induction Mutual induction All of these None 34. If Nₛ/Nₚ = 50, Iₚ = 20A, Vₚ = 220 V, Vₛ =? 1100 V 11000 V 500 V 1000 V None 35. In a step down transformer, the input voltage is 200 voltage and the output voltage is 5 volts the turn ratio of the transformer is: 1:20 1:40 20:1 40:1 None 36. The main cause of power loss in transformers is: Hysteresis Eddy current Both a and b None of these None 37. The coils of a transformer are: Magnetically linked Electrically linked Both A and B None of these None 38. A transformer has: Two coil Only one coil Works on the principle of mutual induction None of these None 39. The output of a dynamo using a split ring commutator is: Half wave rectified voltage A.C D.C Fluctuating D.C None 40. The windings of an electromagnet used in motors are called: Armature coil Primary coil Secondary coil Field coils None 1 out of 8 Thanks For Taking This Quiz - Please See Your Answers/Results Below After Entering Your Name & Email... Name Email Time's up
