Chapter 25: Electromagnetic Induction

33 Questions | Total Attempts: 3053

SettingsSettingsSettings
Chapter 25: Electromagnetic Induction - Quiz

.


Questions and Answers
  • 1. 
    When there is a change in the magnetic field in a closed loop of wire
    • A. 

      a voltage is induced in the wire.

    • B. 

      A current is created in the loop of wire.

    • C. 

      Electromagnetic induction occurs.

    • D. 

      All of these

    • E. 

      None of these

  • 2. 
    Thrust a magnet into a coil of wire and the coil
    • A. 

      Becomes an electromagnet.

    • B. 

      Has a current in it.

    • C. 

      Both of these

    • D. 

      Neither of these

  • 3. 
    When a bar magnet is thrust into a coil of copper wire, the coil tends to
    • A. 

      Attract the magnet as it enters.

    • B. 

      Repel the magnet as it enters.

    • C. 

      Both of these

    • D. 

      Neither of these

  • 4. 
    Electromagnetic induction occurs in a coil when there is a change in
    • A. 

      Electric field intensity in the coil.

    • B. 

      Magnetic field intensity in the coil.

    • C. 

      Voltage in the coil.

    • D. 

      The coil's polarity.

    • E. 

      Electromagnetic polarity.

  • 5. 
    Voltage can be induced in a wire by
    • A. 

      Moving the wire near a magnet.

    • B. 

      Moving a magnet near the wire.

    • C. 

      Changing the current in a nearby wire.

    • D. 

      Choices A, B, and C are all true.

    • E. 

      None of the above choices are true.

  • 6. 
    A wire moving at right angles to a magnetic field has NO induced voltage
    • A. 

      If it is made of copper.

    • B. 

      If it is moving slowly.

    • C. 

      If it is moving very fast.

    • D. 

      If the wire is covered with insulation.

    • E. 

      None of the above choices are correct.

  • 7. 
    The magnetic field strength inside a current-carrying coil will be greater if the coil encloses a
    • A. 

      Vacuum.

    • B. 

      Wooden rod.

    • C. 

      Glass rod.

    • D. 

      Rod of iron.

    • E. 

      None of these

  • 8. 
    If a magnet is pushed into a coil, voltage is induced across the coil. If the same magnet is pushed into a coil with twice the number of loops
    • A. 

      One half as much voltage is induced.

    • B. 

      The same voltage is induced.

    • C. 

      Twice as much voltage is induced.

    • D. 

      Four times as much voltage is induced.

    • E. 

      None of these

  • 9. 
    An electric motor is very similar to
    • A. 

      An electric generator.

    • B. 

      An automobile battery.

    • C. 

      A radio receiver.

    • D. 

      None of the above choices are correct.

  • 10. 
    A device that transforms electrical energy to mechanical energy is a
    • A. 

      Generator.

    • B. 

      Motor.

    • C. 

      Transformer.

    • D. 

      Magnet.

    • E. 

      None of these

  • 11. 
    A device that transforms mechanical energy into electrical energy is a
    • A. 

      Generator.

    • B. 

      Motor.

    • C. 

      Transformer.

    • D. 

      Magnet.

    • E. 

      None of these

  • 12. 
    If the voltage produced by a generator alternates, it does so because
    • A. 

      Unlike a battery, it produces alternating current.

    • B. 

      The changing magnetic field that produces it alternates.

    • C. 

      Alterations in the mechanical energy input.

    • D. 

      In effect it is an ac motor in reverse.

    • E. 

      The current it produces alternates.

  • 13. 
    A principle difference between an MHD generator and a conventional generator is that the MHD generator
    • A. 

      Has no moving parts.

    • B. 

      Operates more efficiently at high temperatures.

    • C. 

      Choices A and B are both true.

    • D. 

      Choices A and B are both false.

  • 14. 
     A transformer actually transforms
    • A. 

      Voltage.

    • B. 

      Magnetic field lines.

    • C. 

      Generators into motors.

    • D. 

      Non-safe forms of energy to safe forms of energy.

    • E. 

      All of the above choices are correct.

  • 15. 
    The primary of a transformer is the coil connected to
    • A. 

      The load.

    • B. 

      The Internet.

    • C. 

      The power line.

    • D. 

      None of these

  • 16. 
    Transformers use ac so there will be the required
    • A. 

      Transfer of energy from coil to coil.

    • B. 

      Voltage for transformation.

    • C. 

      Change in magnetic field for operation.

    • D. 

      Change in input current.

    • E. 

      Magnetic field intensities.

  • 17. 
    Compared to the primary voltage, the secondary voltage may be
    • A. 

      Larger.

    • B. 

      Smaller.

    • C. 

      The same.

    • D. 

      The same or smaller, but not larger.

    • E. 

      Larger, smaller, or the same.

  • 18. 
    The output power of an ideal transformer is
    • A. 

      Greater than the input power.

    • B. 

      Equal to the input power.

    • C. 

      Smaller than the input power.

    • D. 

      May be any of these

  • 19. 
    Disconnect a small-voltage battery from a coil of many loops of wire and a large voltage is produced by
    • A. 

      The sudden collapse in the magnetic field.

    • B. 

      Latent energy in the battery.

    • C. 

      The resistance of the battery to a change in polarity.

    • D. 

      Electrons already in the wire.

    • E. 

      The electric field between the battery terminals.

  • 20. 
    Power is transmitted at high voltages because the corresponding current in the wires is
    • A. 

      Also high to deliver appreciable power to distant places.

    • B. 

      Low so that overheating of the wires is minimized.

    • C. 

      Choices A and B are both true.

    • D. 

      Choices A and B are both false.

  • 21. 
    Rapid change of a magnetic field induces
    • A. 

      A magnetic field of greater magnitude.

    • B. 

      A magnetic field of the same magnitude.

    • C. 

      An electric field.

  • 22. 
    The metal detectors that people walk through at airports operate via
    • A. 

      Ohm's law.

    • B. 

      Faraday's law.

    • C. 

      Coulomb's law.

    • D. 

      Newton's laws.

    • E. 

      Civil laws.

  • 23. 
    A step-up transformer increases
    • A. 

      Power.

    • B. 

      Energy.

    • C. 

      Both power and energy.

    • D. 

      Neither power or energy.

  • 24. 
    A step-up transformer has a ratio of one to ten. Neglecting slight losses, if 100 W of power go into the primary coil, the power coming from the secondary coil is
    • A. 

      1 W.

    • B. 

      10 W.

    • C. 

      100 W.

    • D. 

      1000 W.

    • E. 

      None of these

  • 25. 
    A certain transformer doubles input voltage. If the primary coil has 10 A of current, then the current in the secondary coil is
    • A. 

      2 A.

    • B. 

      5 A.

    • C. 

      10 A.

    • D. 

      25 A.

    • E. 

      None of these

Back to Top Back to top
×

Wait!
Here's an interesting quiz for you.

We have other quizzes matching your interest.