Discussion
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- Question
The amount of time between the creation and recombination of a free electron and hole is called
Options- A. relaxation time
- B. life time
- C. lorentz time
- D. collision time
- Correct Answer
- life time
- 1. Dielectric constant, under the condition of alternating fields, is a complex quantity.
Options- A. True
- B. False Discuss
- 2. A photoconductor is a
Options- A. conductor
- B. semiconductor
- C. insulator
- D. superconductor Discuss
- 3. The probability of recombination of electrons and holes in a semiconductor is proportional to
Options- A. density of electrons
- B. density of holes
- C. density of electrons and holes
- D. none of the above Discuss
- 4. In a valence crystal, the valence electrons
Options- A. are not shared
- B. are shared between neighbouring atoms
- C. are shared by all atoms
- D. any of the above Discuss
- 5. For iron, the ferromagnetic Curie temperature is
Options- A. about 20 K
- B. about 100°C
- C. about -20°C
- D. about 1000 K Discuss
- 6. In ferromagnetic materials, the orientation between neighbouring permanent dipoles is parallel.
Options- A. True
- B. False Discuss
- 7. As regards dielectric constant ?r
Options- A. the units are farads/m
- B. the units are newton/coulomb
- C. it is dimensionless
- D. the units are farads Discuss
- 8. Assertion (A): Electron concentration n, hole concentration p and charge concentration ni are related by ni2 = np.
Reason (R): p type semiconductor is obtained by adding trivalent impurity to intrinsic semiconductor.
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. Which of the following statement about the advantage of phase discriminator over the slope detector is false?
Options- A. Fewer tuned circuits
- B. Better linearity
- C. Greater limiting
- D. Much easier alignment Discuss
- 10. High IF in a superheat receiver
Options- A. improves selectivity
- B. increases tracking problems
- C. decreases tracking problems
- D. reduces adjacent channel rejection Discuss
Materials and Components problems
Search Results
Correct Answer: True
Correct Answer: semiconductor
Correct Answer: density of electrons and holes
Correct Answer: are shared between neighbouring atoms
Explanation:
In true valence crystals the binding between the atoms is accomplished by the sharing of valence electrons.
This sharing can only be between neighbouring atoms only.
Correct Answer: about 1000 K
Correct Answer: True
Correct Answer: it is dimensionless
Explanation:
?r is only a number and does not have any units.
Correct Answer: Both A and R are true but R is not correct explanation of A
Correct Answer: Greater limiting
Correct Answer: increases tracking problems
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