Questions and answers for exam Preparation

MCQs

Total Questions : 848 | Page 6 of 85 pages

Question 51. A-P type material has an acceptor ion concentration of 1 x 10¹⁶ per cm³. Its intrinsic carrier concentration is 1.48 x 10¹ᴼ/ cm. The hole and electron mobilities are 0.05m²/V-sec and 0.13 m²/V-sec respectively calculate the resistivity of the material

12.5 Ω-cm
1.25 Ω-cm
0.125 Ω-cm
125 Ω-cm

Discuss Question

Answer: Option B. -> 1.25 Ω-cm
Answer: (b).1.25 Ω-cm

Question 52. Operating point signifies that

zero signal IC and VBE
zero signal IC and VCE
zero signal IB and VCE
zero signal IC, VCE

Discuss Question

Answer: Option B. -> zero signal IC and VCE
Answer: (b).zero signal IC and VCE

Question 53. Resistivity is a property of a semiconductor that depends on

the atomic weight of the semiconductor
the atomic number of the semiconductor
the atomic nature of the semiconductor
the shape of the semiconductor

Discuss Question

Answer: Option C. -> the atomic nature of the semiconductor
Answer: (c).the atomic nature of the semiconductor

Question 54. For a junction FET in the pinch off region as the drain voltage is increased, the drain current

becomes zero
abruptly decreases
abruptly increases
remains constant

Discuss Question

Answer: Option D. -> remains constant
Answer: (d).remains constant

Question 55. When a normal atom loses an electron

the atom loses one-proton simultaneously
rest of the electrons move faster
the atom becomes a positive ion
the atom becomes a negative ion

Discuss Question

Answer: Option C. -> the atom becomes a positive ion
Answer: (c).the atom becomes a positive ion

Question 56. A sample of N-type semiconductor has electron density of 6.25 x 10¹⁸/cm³ at 300k. If the intrinsic concentration of carriers in this sample is 2.5 x 10¹³/cm³ at this temperature the hole density works out to be

10⁶/cm³
10⁸/cm³
10¹ᴼ/cm³
10¹²/cm³

Discuss Question

Answer: Option B. -> 10⁸/cm³
Answer: (b).10⁸/cm³

Question 57. Mobility is directly proportional to Hall coefficient.

True
False
May be True or False
Can't say

Discuss Question

Answer: Option A. -> True
Answer: (a).True

Question 58. N channel FETs are better as compared to p-channel FET because

they are more efficient
they have high switching time
they have higher input impedance
mobility of electrons is more than that of holes

Discuss Question

Answer: Option D. -> mobility of electrons is more than that of holes
Answer: (d).mobility of electrons is more than that of holes

Question 59. An n channel depletion type MOSFET has

lightly doped p substrate and highly doped n source and drain
highly doped p substrate and highly doped n source and drain
highly doped p substrate and lightly doped n source and drain
lightly doped n substrate and highly doped n source and drain

Discuss Question

Answer: Option A. -> lightly doped p substrate and highly doped n source and drain
Answer: (a).lightly doped p substrate and highly doped n source and drain

Question 60. In a JFET avalanche breakdown occurs when VDS = 22 V and VGS = 0. If VGS = -1 V, the avalanche breakdown will occur at