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  • Question
  • Which of the following are donor impurities?

    1. Gold
    2. Phosphorus
    3. Boron
    4. Antimony
    5. Arsenic
    6. Induim
    Select the correct answer using the following codes


  • Options
  • A. 1, 2, 3
  • B. 1, 2, 4, 6
  • C. 3, 4, 5, 6
  • D. 2, 4, 5

  • Correct Answer
  • 2, 4, 5 

    Explanation
    Donor impurities have five valence electrons.

    Materials and Components problems


    Search Results


    • 1. Assertion (A): Atomic number of sodium is 11.

      Reason (R): Sodium has a body centred cubic lattice.


    • Options
    • 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
    • Discuss
    • 2. At room temperature, the current in intrinsic semiconductor is due to

    • Options
    • A. holes
    • B. electrons
    • C. ions
    • D. holes and electrons
    • Discuss
    • 3. Ferroelectric materials are those which

    • Options
    • A. cannot be polarized
    • B. have a permanent polarization
    • C. have ae equal to zero
    • D. have ?p = 0
    • Discuss
    • 4. The apparent capacitance at a high angular frequency ? of an air cored capacitor having capacitance C and inductance L is given by

    • Options
    • A.
    • B.
    • C.
    • D.
    • Discuss
    • 5. In paramagnetic materials

    • Options
    • A. permanent magnetic dipoles exist but the interaction between neighbouring dipoles is negligible
    • B. permanent magnetic dipole do not exist
    • C. permanent magnetic dipoles exist and the interaction between neighbouring dipoles is very strong
    • D. permanent magnetic dipole moment may or may not exist
    • Discuss
    • 6. Assertion (A): Power loss in a conductor of resistance P = I2R.

      Reason (R): When a conductor is carrying current with current density J as a result of applied field E, then heat developed/m3/ second = JE.


    • Options
    • 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
    • Discuss
    • 7. When an electric field E is applied to solid and liquid insulating materials, the internal field Ei acting at the location of atom is such that

    • Options
    • A. Ei = E
    • B. Ei > E
    • C. Ei < E
    • D. Ei may be equal to or less than E
    • Discuss
    • 8. The number of valence electrons in donor impurity are

    • Options
    • A. 5
    • B. 4
    • C. 3
    • D. 1
    • Discuss
    • 9. Assertion (A): In imperfect capacitors, the current does not lead the applied ac voltage by 90°.

      Reason (R): When subjected to ac fields, the dielectric constant can be expressed as ?'r - j?"r.


    • Options
    • 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
    • Discuss
    • 10. Assertion (A): Ferroelectric materials have spontaneous polarization.

      Reason (R): Above curie temperature, ? = for ferro-electric materials.


    • Options
    • 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
    • Discuss


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