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  • Question

  • The specific gravity of tungsten is 13.8 and its atomic weight is 184.0 Assume that there are two free elements per atom. Then the Fermi level or characteristic energy for the crystal in eV will be


  • Options
  • A. 8.95 eV
  • B. -8.95 eV
  • C. 7.326 eV
  • D. -7.326 eV

  • Correct Answer
  • 7.326 eV 

    Explanation
    A quantity of any substance equal to its molecular weight in grams is a mole of that substance contains the same number of molecules as one mole of any other substance. This Avogadro's number and equals 6.02 x 1023 molecules per mole. Thus

    The specific gravity of tungsten is 13.8 and its atomic weight is 184.0 Assume that there are two fr

    The specific gravity of tungsten is 13.8 and its atomic weight is 184.0 Assume that there are two fr

    The specific gravity of tungsten is 13.8 and its atomic weight is 184.0 Assume that there are two fr

    = 9.03 x 1028 electrons/m3

    Since for tungsten the atomic and the molecular weights are the same. Therefore for tungsten

    EF = 3.64 x 10-19(?)2/3

    = 3.64 x 10- 19(9.03 x 1028)2/3

    EF = 7.326 eV.

    More questions

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    • Options
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    • 2. For a 1 cm x 2 cm air filled rectangular waveguide the maximum frequency should be less than about

    • Options
    • A. 1000 MHz
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    • Options
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    • Options
    • A. 5
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      Reason (R): A DIAC can conduct in both directions.


    • Options
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