This is a review exercise. Underline all the correct answers. Explain why an ans

Question

This is a review exercise. Underline all the correct answers. Explain why an answer is correct or why it is wrong.

Problem 1. A metal is at 0K, the valence and conduction band are

(I)

Both are completely empty

Both are completely filled.

Both are partially empty.

Both are partially filled.

None of the above

All of the above 1-4.

(II)

CB band is completely empty and VB is completely filled.

VB band is completely empty and CB is completely filled.

CB band is partially empty and VB is completely filled.

VB band is partially empty and CB is completely filled.

None of the above

All of the above (1-4)

(III)

CB band is partially filled and VB is completely filled.

VB band is partially filled and CB is completely filled.

CB band is partially empty and VB is partially filled.

VB band is partially empty and CB is partially filled.

None of the above

All of the above (1-4)

Problem 2. A metal is at 300K, the valence and conduction band are

(I)

Both are completely empty

Both are completely filled.

Both are partially empty.

Both are partially filled.

None of the above

All of the above 1-4.

(II)

CB band is completely empty and VB is completely filled.

VB band is completely empty and CB is completely filled.

CB band is partially empty and VB is completely filled.

VB band is partially empty and CB is completely filled.

None of the above

All of the above (1-4)

(III)

CB band is partially filled and VB is completely filled.

VB band is partially filled and CB is completely filled.

CB band is partially empty and VB is partially filled.

VB band is partially empty and CB is partially filled.

None of the above

All of the above (1-4)

Problem 3. A metal is at 500K (the material did not breakdown), the valence and conduction band are

(I)

Both are completely empty

Both are completely filled.

Both are partially empty.

Both are partially filled.

None of the above

All of the above 1-4.

(II)

CB band is completely empty and VB is completely filled.

VB band is completely empty and CB is completely filled.

CB band is partially empty and VB is completely filled.

VB band is partially empty and CB is completely filled.

None of the above

All of the above (1-4)

(III)

CB band is partially filled and VB is completely filled.

VB band is partially filled and CB is completely filled.

CB band is partially empty and VB is partially filled.

VB band is partially empty and CB is partially filled.

None of the above

All of the above (1-4)

Problem 4. An insulator at 0K, the valence and conduction band are

(I)

Both are completely empty

Both are completely filled.

Both are partially empty.

Both are partially filled.

None of the above

All of the above 1-4.

(II)

CB band is completely empty and VB is completely filled.

VB band is completely empty and CB is completely filled.

CB band is partially empty and VB is completely filled.

VB band is partially empty and CB is completely filled.

None of the above

All of the above (1-4)

(III)

CB band is partially filled and VB is completely filled.

VB band is partially filled and CB is completely filled.

CB band is partially empty and VB is partially filled.

VB band is partially empty and CB is partially filled.

None of the above

All of the above (1-4)

Problem 5. An insulator at 300K, the valence and conduction band are

(I)

Both are completely empty

Both are completely filled.

Both are partially empty.

Both are partially filled.

None of the above

All of the above 1-4.

(II)

CB band is completely empty and VB is completely filled.

VB band is completely empty and CB is completely filled.

CB band is partially empty and VB is completely filled.

VB band is partially empty and CB is completely filled.

None of the above

All of the above (1-4)

(III)

CB band is partially filled and VB is completely filled.

VB band is partially filled and CB is completely filled.

CB band is partially empty and VB is partially filled.

VB band is partially empty and CB is partially filled.

None of the above

All of the above (1-4)

Problem 6. An insulator at 500K, the valence and conduction band are

(I)

Both are completely empty

Both are completely filled.

Both are partially empty.

Both are partially filled.

None of the above

All of the above 1-4.

(II)

CB band is completely empty and VB is completely filled.

VB band is completely empty and CB is completely filled.

CB band is partially empty and VB is completely filled.

VB band is partially empty and CB is completely filled.

None of the above

All of the above (1-4)

(III)

CB band is partially filled and VB is completely filled.

VB band is partially filled and CB is completely filled.

CB band is partially empty and VB is partially filled.

VB band is partially empty and CB is partially filled.

None of the above

All of the above (1-4)

Problem 7. If photons with energy of 1.7 eV was applied to an insulator with Eg=9 eV, the valence and conduction band are

(I)

Both are completely empty

Both are completely filled.

Both are partially empty.

Both are partially filled.

None of the above

All of the above 1-4.

(II)

CB band is completely empty and VB is completely filled.

VB band is completely empty and CB is completely filled.

CB band is partially empty and VB is completely filled.

VB band is partially empty and CB is completely filled.

None of the above

All of the above (1-4)

(III)

CB band is partially filled and VB is completely filled.

VB band is partially filled and CB is completely filled.

CB band is partially empty and VB is partially filled.

VB band is partially empty and CB is partially filled.

None of the above

All of the above (1-4)

Problem 7. If photons with energy of 3.7 eV was applied to an insulator with Eg=3 eV, assuming no breakdown takes place, the valence and conduction band are

(I)

Both are completely empty

Both are completely filled.

Both are partially empty.

Both are partially filled.

None of the above

All of the above 1-4.

(II)

CB band is completely empty and VB is completely filled.

VB band is completely empty and CB is completely filled.

CB band is partially empty and VB is completely filled.

VB band is partially empty and CB is completely filled.

None of the above

All of the above (1-4)

(III)

CB band is partially filled and VB is completely filled.

VB band is partially filled and CB is completely filled.

CB band is partially empty and VB is partially filled.

VB band is partially empty and CB is partially filled.

None of the above

All of the above (1-4)

  

Explanation / Answer

At 0k valance band is completely filled and conduction band is wmpty because at absoute zero temp valence band is full and no electron has energy that it can cross potential barrier and go to conductio band.

At 300k valance band and conduction badn are partially filled and the contect upto which they are filled depende on energy gap present between these two bands.

At 500k at this high temp compare to above case valance is has less electron and conduction band has more electron.Because at this temp elecctron gain much energy and can cross potential barriee.

In insulater this energy gap is very high so at 0 aor rvrn at higher temp range most of elecron remain at valace band.

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.