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ECE :: Materials and Components

  1. A leakage capacitor can be represented by a capacitance C and resistance R in parallel C.

  2. A.
    True
    B.
    False

  3. Electric dipole moment is expressed in debye unit.

  4. A.
    True
    B.
    False

  5. A vacant electronic state moves in the same direction as would a positive charge carrier.

  6. A.
    True
    B.
    False

  7. Piezoelectricity means the slight change in dimensions of a specimen when an electric field is applied.

  8. A.
    True
    B.
    False

  9. Many compounds also exhibit semiconducting properties.

  10. A.
    True
    B.
    False

  11. For magnetic shielding, we need a ferromagnetic material.

  12. A.
    True
    B.
    False

  13. Assertion (A): Electronic polarizability increases as atoms becomes larger.

    Reason (R): For rare gas, ∈0(∈r - 1) E = Nae, where N is number of atoms/m3 and ae is electronic polarizability of material.

  14. A.
    Both A and R are true and R is correct explanation of A
    B.
    Both A and R are true but R is not correct explanation of A
    C.
    A is true but R is false
    D.
    A is false but R is true

  15. In a metal, the valence electrons

  16. A.
    are not shared
    B.
    are shared only between neighbouring atoms
    C.
    are shared by all atoms
    D.
    either (b) or (c)

  17. All magnetic materials exhibit the phenomenon of saturation.

  18. A.
    True
    B.
    False

  19. In p type semiconductor, the conductivity due to holes is (e = charge on hole, μp = hole mobility, p = hole concentration)

  20. A.
    B.
    C.
    peμp
    D.