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  1. High resistivity materials are used in

  2. A.

     Precision instruments

    B.

     Heating elements

    C.

     Motor starters

    D.

     Incandescent lamps

    E.

     All of the above


  3. Low resistivity materials are used in

  4. A.

     Transformer, motor and generator windings

    B.

     Transmission and distribution lines

    C.

     House wiring

    D.

     All above applications


  5. Most of the common metals have _________ structure.

  6. A.

     Linear

    B.

     Hexagonal

    C.

     Orthorhombic

    D.

     Cubic


  7. Which of the following materials does not have covalent bonds ?

  8. A.

     Organic polymers

    B.

     Silicon

    C.

     Metals

    D.


  9. For germanium the forbidden energy gap is

  10. A.

     0.15 eV

    B.

     0.25 eV

    C.

     0.5eV

    D.

     0.7eV


  11. Thermonic emission occurs in

  12. A.

     Vacuum tubes

    B.

     Copper conductors

    C.

     Ferrite cores

    D.

     Transistors


  13. Copper, even though costly, finds use in the windings of electrical machines because

  14. A.

     Copper points offer low contact resistance

    B.

     Copper can be easily soldered and welded

    C.

     Copper windings are less bulky and the machines become compact

    D.

     All of the above


  15. _______ has zero temperature co-efficient of resistance.

  16. A.

     Aluminium

    B.

     Carbon

    C.

     Porcelain

    D.

     Manganin


  17. Which of the following is a semiconductor material ?

  18. A.

     Phosphorous

    B.

     Rubber

    C.

     Silicon

    D.

     Aluminium


  19. Constantan contains

  20. A.

     Silver and tin

    B.

     Copper and tungsten

    C.

     Tungsten and silver

    D.

     Copper and nickel