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  • Question

  • Assertion (A): In ionic dielectrics, P = Pe + Pi.

    Reason (R): In ionic crystals, permanent electric dipole moment is zero.


  • 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

  • Correct Answer
  • Both A and R are true and R is correct explanation of A 

    Explanation
    In ionic dielectrics ?p = ?i ei ri and Po = 0.

    Therefore P = Pe + Pi.

    Materials and Components problems

    Search Results

    • 1. The current flow in a semiconductor is due to

    • Options
    • A. holes
    • B. electrons
    • C. holes and electrons
    • D. holes, electrons and ions
      • Discuss
    • 2. The dipole moment per unit volume P as a function of E for an insulator is

    • Options
    • A. P = ?0 E(?r)
    • B. P = ?0 E
    • C. P = ?0(?r - 1) E
    • D. P =
      • Discuss
    • 3. Assertion (A): In liquids and glassy substances, dielectric losses occur.

      Reason (R): The orientation polarization in many substances is frequency dependent.


    • 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
    • 4. Consider the following statement: In case of a superconductor

      1. B = 0
      2. ?r is high
      3. diamagnetism is high
      4. transition temperature varies with isotopic mass.
      Of the above statements

    • Options
    • A. 1 and 2 are correct
    • B. 2, 3, 4 are correct
    • C. 1, 3, 4 are correct
    • D. 2, 4 are correct
      • Discuss
    • 5. Eddy current loss is

    • Options
    • A. proportional to frequency
    • B. independent of frequency
    • C. proportional to (frequency)2
    • D. proportional to (frequency)3
      • Discuss
    • 6. A copper atom is neutral. Its core has a net charge of

    • Options
    • A. 0
    • B. + 1
    • C. - 1
    • D. + 2
      • Discuss
    • 7. A parallel plate capacitor has area of plate A and plate separation d. Its capacitance is C. A metallic plate P of area A and negligible thickness is added as shown in Figure. The new value of capacitance is

    • Options
    • A. C
    • B. 2C
    • C. 0.5 C
    • D. 0.25 C
      • Discuss
    • 8. Assertion (A): In an intrinsic semiconductor J = (?n x ?p)eni.

      Reason (R): Intrinsic charge concentration ni at temperature T is given by ni2 = A0 T3 e-EG0/kT.


    • 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
    • 9. A good dielectric should have

    • Options
    • A. low losses
    • B. good heat conductivity
    • C. high intrinsic strength
    • D. all of the above
      • Discuss
    • 10. The temperature coefficient of resistivity of semiconductors is

    • Options
    • A. positive
    • B. negative
    • C. may be positive or negative
    • D. very low
      • Discuss

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