NTA UGC NET/JRF Exam, June -2020 (Electronic Science)

Total Questions: 100

61. A differential transformer

(a) is a differential voltage of two secondary windings of a transformer is varied by positioning the magnetic core through an externally applied force
(b) is used for pressure measurement
(c) is used for force measurement
(d) is used for displacement measurement
(e) is used for position measurement
Choose the correct answer from the options given below:

Correct Answer: D. (a), (b), (c), (d), (e) only

62. The wheatstone bridge is widely used for precision measurement of resistance:

(a) from 1 Ω to few ΜΩ
(b) very low resistance
(c) very high resistance
(d) 1 mΩ -10 ΚΩ (e) 0.1 Ω - 100 ΚΩ
Choose the correct answer from the options given below:

Correct Answer: A. (a) only

63. The Schering bridge, one of the most important AC bridge:

(a) It is used for capacitance measurement
(b) It is used for phase angle measurement
(c) It is used for inductance measurement
(d) It is used for resistance measurement
(e) It is used for torque measurement
Choose the correct answer from the options given below:

Correct Answer: A. (a) and (b) only

64. For the unit step response of second order system following statements are given:

(a) Delay time is the time required for the response to reach 60% of the final value in first attempt
(b) Settling time is the time required for the response to reach and stay within (2% or 5%) tolerance band of its final value
(c) Delay time is the time required for the response to reach 50% of the final value in first attempt
(d) Settling time is the time required for the response to reach and stay within 15% of the final value Which of the above are correct?
Choose the correct answer from the options given below:

Correct Answer: B. (b) and (c) only

65. A unity feedback system as shown has damping ratio of 0.8 using derivative control

Following parameters are obtained
(a) Characteristic equation is s² + 1.6s+ 16 = 0
(b) ξ = 0.2 (without derivative control)
(c) ξ = 0.8 (without derivative control)
(d) ξ = 4 rad/sec
Choose the most appropriate answer from the options given below:

Correct Answer: C. (a), (b), (d) only

66. Match List-I with List-II

Choose the correct answer from the options given below:

(a)(b)(c)(d)
A.(i)(ii)(iii)(iv)
B.(iv)(iii)(i)(ii)
C.(ii)(i)(iv)(iii)
D.(iii)(iv)(ii)(i)
Correct Answer: B.

67. Match List-I with List-II

List-IList-II
(Diffusion profile measurement technique)(Characteristics)
(a) Capacitance - voltage(i) Not suitable for diffusion studies in VLSI process when shallow junction profile are of interest
(b) Differential-conductance(ii) Needs Van de graff generator
(c) Spreading resistance(iii) Two-point probe arrangement
(d) RBS(iv) Concentration near the junction space - charge region at zero bias cannot be measured

Choose the correct answer from the options given below:

(a)(b)(c)(d)
A.(i)(ii)(iv)(iii)
B.(iv)(i)(iii)(ii)
C.(iii)(iv)(ii)(i)
D.(ii)(iii)(i)(iv)
Correct Answer: B.

68. Match List-I with List-II

Choose the correct answer from the options given below:

(a)(b)(c)(d)
A.(iv)(ii)(i)(iii)
B.(ii)(i)(iv)(iii)
C.(ii)(iii)(i)(iv)
D.(iii)(i)(ii)(iv)
Correct Answer: D.

69. Match List-I with List-II

Choose the correct answer from the options given below:

(a)(b)(c)(d)
A.(ii)(iii)(i)(iv)
B.(ii)(iii)(iv)(i)
C.(iii)(ii)(iv)(i)
D.(iii)(i)(ii)(iv)
Correct Answer: D.

70. Match List-I with List-II

List-IList-II
(a) Simplest type of ADC(i) Flash-type ADC
(b) Fastest ADC(ii) dual-slope type ADC
(c) Slowest ADC(iii) counter - type ADC
(d) Most widely used ADC(iv) Successive-approximation type ADC

Choose the correct answer from the options given below:

(a)(b)(c)(d)
A.(iii)(i)(ii)(iv)
B.(ii)(iv)(i)(iii)
C.(iv)(ii)(iii)(i)
D.(iii)(iv)(ii)(i)
Correct Answer: A.