Home / EEE / Magnetic Circuit :: section-1

EEE :: Magnetic Circuit

  1. While comparing magnetic and electric circuits, the flux of magnetic circuit is compared with which parameter of electrical circuit?

  2. A.

     E.M.F.

    B.

     Current

    C.

     Current density

    D.

     Conductivity

    View Answer

    Workspace

    Discuss Discuss in Forum


  3. Point out the wrong statement. Magnetic leakage is undesirable in electric machines because it

  4. A.

     Lowers their power efficiency

    B.

     Increases their cost of manufacture

    C.

     Leads to their increased weight

    D.

     Produces fringing

    View Answer

    Workspace

    Discuss Discuss in Forum


  5. The unit of magnetic flux is

  6. A.

     Henry

    B.

     Weber

    C.

     Ampere-turn/weber

    D.

     Ampere/metre

    View Answer

    Workspace

    Discuss Discuss in Forum


  7. Laminated cores, in electrical machines, are used to reduce

  8. A.

     Copper loss

    B.

     Eddy current loss

    C.

     Hysteresis loss

    D.

     All of the above

    View Answer

    Workspace

    Discuss Discuss in Forum


  9. Those materials are well suited for making permanent magnets which have ________ retentivity and ________ coercivity.

  10. A.

     Low, high

    B.

     High, high

    C.

     High, low

    D.

     Low, low

    View Answer

    Workspace

    Discuss Discuss in Forum


  11. Those magnetic materials are best suited for making armature and transformer cores which have ________permeability and _________hysteresis loss.

  12. A.

     High, high

    B.

     Low, high

    C.

     High, low

    D.

     Low, low

    View Answer

    Workspace

    Discuss Discuss in Forum


  13. The initial rate of rise of current through a coil of inductance 10 H when suddenly connected to a D.C. supply of 200 V is ___________Vs

  14. A.

     50

    B.

     20

    C.

     0.05

    D.

     500

    View Answer

    Workspace

    Discuss Discuss in Forum


  15. Relative permeability of vacuum is

  16. A.

     1

    B.

     1 H/m

    C.

     1/4JI

    D.

     4n × 10' H/m

    View Answer

    Workspace

    Discuss Discuss in Forum


  17. In a magnetic material hysteresis loss takes place primarily due to

  18. A.

     Rapid reversals of its magnetization

    B.

     Flux density lagging behind magnetizing force

    C.

     Molecular friction

    D.

     It high retentivity

    View Answer

    Workspace

    Discuss Discuss in Forum


  19. Permeability in a magnetic circuit corresponds to_________ in an electric circuit.

  20. A.

     Resistance

    B.

     Resistivity

    C.

     Conductivity

    D.

     Conductance

    View Answer

    Workspace

    Discuss Discuss in Forum