logo

CuriousTab

CuriousTab

Discussion


Home Electronics and Communication Engineering Materials and Components Comments

  • Question
  • Semi conducting materials are all


  • Options
  • A. elements
  • B. compounds
  • C. elements or compounds
  • D. elements or mixtures

  • Correct Answer
  • elements or compounds 

    Explanation
    Many compounds also show semiconducting properties.

    Materials and Components problems


    Search Results


    • 1. Assertion (A): In Figure, the intercept of the line on y-axis is equal to N (ae + ai), where N is number of atoms/m3, ae is electronic polarizability and ai is ionic polarizability.

      Reason (R): ae and ai are independent of temperature.


    • 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. Assertion (A): If difference between static and optical dielectric constant is high, the mechanical compressiblity of that material is also high.

      Reason (R): For soft ions, ionic polarization per unit field is higher than that of hard ions.


    • 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
    • 3. A piece of iron is placed in a magnetic field

    • Options
    • A. the magnetic field will not be affected
    • B. the magnetic lines of force will bend to pass through the piece
    • C. the magnetic lines of force will bend away from the piece
    • D. any of the above depending on type of iron
    • Discuss
    • 4. In a piezoelectric crystal, the application of mechanical force will cause

    • Options
    • A. plastic deformation of crystal
    • B. magnetic dipoles in the crystal
    • C. electrical polarization in the crystal
    • D. shift in Fermi level
    • Discuss
    • 5. Orbital magnetic dipole moment is due to the motion of electron in its orbit around nucleus.

    • Options
    • A. True
    • B. False
    • Discuss
    • 6. In a metal, the drift velocity of electrons in the presence of a electric field E is

    • Options
    • A. proportional to E
    • B. proportional to E
    • C. inversely proportional to E
    • D. proportional to E2
    • Discuss
    • 7. Inductors used at V.H.F. are made using

    • Options
    • A. air core
    • B. cast iron cored
    • C. sheet steel cored
    • D. thin film technique
    • Discuss
    • 8. Assertion (A): The resistance of a copper specimen changes by about 22% when temperature is increased from room temperature to 700°C.

      Reason (R): The physical properties of a material are determined mostly by the extent of impurities.


    • 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. Assertion (A): For elemental dielectrics, P = NaeEi where N is number of atoms/m3, P is polarization, ae is electronic polarization and Ei is internal electric field.

      Reason (R): In elemental dielectrics there are no permanent dipoles or ions.


    • 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. The dielectric constant of ferroelectric materials can be expressed by the equation

    • Options
    • A.
    • B.
    • C.
    • D.
    • Discuss


    Comments

    There are no comments.

Enter a new Comment