NTA UGC NET/JRF Exam, June-2019 (Electronic Science)

Total Questions: 100

51. In a Zener diode shunt voltage regulator, the diode regulates so long as is kept in:

(a) forward condition
(b) reverse condition
(c) loaded condition
(d) unloaded condition
Choose the correct option:

Correct Answer: B. (b) is correct, but (d) is wrong

52. The field effect transistor has:

(a) very high input resıstance
(b) high electrical noise
(c) low input resistance
(d) low electrical noise
Choose the correct option:

Correct Answer: A. (a) and (d) are correct

53. The evaporating rate R from a clean surface is related to the equilibrium vapour pressure Pₑ (in pascal) of the evaporating species (M is the molecular weight in gm) by a relation:

Choose the correct option:

Correct Answer: A. (a) is correct, but (c) is wrong

54. In a p-n junction solar cell under low injection condition, the one-dimensional continuity equations are

Choose the correct option:

Correct Answer: C. (a) and (c) are correct

55. Transfer function of an electrical low pass RC network are:

(a) RCs|(1 + RCs)
(b) RC|(1 + RCs)
(c) 1/(1 + RCs)
(d) s/(1+ RCs)
Choose the correct option:

Correct Answer: E. (*)

56. Nodal method of circuit analysis is based on:

(a) KVL and Ohm's law
(b) KVL, KCL and Ohm's law
(c) KCL and KVL
(d) KCL and Ohm's law
Which of the following options is correct?

Correct Answer: D. (d) is correct, but (b) is wrong

57. Thermal runaway in a transistor biased in the active region is primarily due to:

(a) heating of the transistor
(b) changes in β, which increases with temperature
(c) base emitter voltage Vꭼꭼ which decreases with rise in temperature
(d) change in reverse saturation current due to rise in temperature
Which of the following options is correct?

Correct Answer: D. (c) is wrong and (d) is correct

58. For an RC phase shift oscillator, the following statements are cited:

(a) Amplifier gain is negative
(b) Phase shift introduced by feedback circuit is either 0 or 360°
(c) Amplifier gain is positive
(d) Phase shift introduced by feedback circuit is 180°
Which of the following options is correct?

Correct Answer: C. Both (a) and (d) are correct

59. The preference for NMOS, when compared to other logic families arises:

(a) as it uses more silicon area
(b) as it consumes less static power
(c) as it utilizes smaller silicon area
(d) as it has higher input impedance
Which of the following options is correct?

Correct Answer: C. (c) is correct, but (d) is wrong

60. The following statements are given about programmable logic array PLA:

(a) It is easier to manufacture and program than a PROM and a PLA
(b) It combines the characteristics of a PROM and a PLA by providing both a programmable AND array and a programmable OR array
(c) In a PLA, both AND gates and OR gates have fusible links at the inputs
Choose the correct option:

Correct Answer: D. (a) is false, but both (b) and (c) are true