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General Knowledge :: Physics

  1. Magnetism in materials is due to

  2. A.

     Electrons at rest

    B.

     Circular motion of electrons

    C.

     Protons at rest

    D.

     All neutrons at rest


  3. The method of magnetisation is:

  4. A.

     Hammering a magnet

    B.

     Heating a magnet

    C.

     Passing direct current through it

    D.

     Passing alternating current through it


  5. Magnetic keepers are pieces of

  6. A.

     Nickel

    B.

     Cobalt

    C.

     Steel

    D.

     Soft iron


  7. Curie point is the temperature at which

  8. A.

     Matter becomes radioactive

    B.

     A metal loses magnetic properties.

    C.

     A metal loses conductivity

    D.

     Transmutation of metal occurs.


  9. Tesla is a unit of magnetic :

  10. A.

     Flux

    B.

     Induction

    C.

     Moment

    D.

     Field


  11. The domain theory of magnetism applies to

  12. A.

     Aluminium

    B.

     Copper

    C.

     Silver

    D.

     Cobalt


  13. The paramagnetic theory of magnetism applies to

  14. A.

     Nickel

    B.

     Mercury

    C.

     Iron

    D.

     Platinum


  15. Where should a boat compass be mounted?

  16. A.

     Near magnet

    B.

     Near iron

    C.

     Away from electrical wiring

    D.

     All the above


  17. Which of the following properties is found only in ferromagnetic materials ?

  18. A.

     Susceptibility independent of temperature

    B.

     Point in a particular direction

    C.

     Hysteresis

    D.

     Attracting a magnetic substance


  19. Magnetic field lines about a current-carrying wire

  20. A.

     Circle the wire in closed loops

    B.

     Extend radially from the wire

    C.

     Both of these

    D.

     None of the above