MCQ in Electronic Systems and Design Part 2 | ECE Board Exam

This is the Multiple Choice Questions in Electronic Systems and Design Part 2 of the Series as one of the Electronics Engineering Examination topic. In Preparation for the ECE Board Exam make sure to expose yourself and familiarize in each and every questions compiled here taken from various sources including but not limited to past Board Exam Questions in Electronics Engineering field, Electronics Books, Journals and other Electronics References.

MCQ Topic Outline included in ECE Board Exam Syllabi

6. Electronic Systems and Design

• MCQ in SCR’s, UJT, PUT, TRIAC, DIAC, and other Thyristors
• MCQ in Optoelectronic Devices and Sensors
• MCQ in Transducers, Data Acquisition, and Interfacing Techniques
• MCQ in Programmable Logic Controllers
• MCQ in Design and Integration in Building Management Systems and HVAC Controls,
  Security, Safety, and Surveillance Control Systems, and Audio-Video and Lighting
  Controls
• MCQ in Instrumentation and Control
• MCQ in Welding Systems
• MCQ in Robotic Principles
• MCQ in Bioelectrical Principles

Continue Practice Exam Test Questions Part 2 of the Series

Choose the letter of the best answer in each questions.

51. What is dimensionless parameter of the second-order characteristic equation?

A. Damping ratio

B. Accuracy

C. Efficiency ratio

D. Transfer function ratio

52. What is the ratio of two exponential functions of time called?

A. Transfer function

B. Damping ratio

C. Efficiency

D. Gain

53. A diac is turned on by

A. breakover voltage

B. gate current

C. gate voltage

D. anode current

54. An SCR whose state is controlled by the light falling upon a silicon semiconductor layer of the device.

A. SCS

B. GTO

C. Thyristor

D. LASCR

55. A diac is simply

A. a single junction

B. a three junction device

C. a triac without a gate terminal

D. the SCR

56. What region lies between the peak point and valley point of UJT emitter characteristic?

A. Saturation

B. Cut off

C. Negative resistance

D. Positive resistance

57. What refers to the application of electronic theory, technology, instrumentation, and computing system to biological research and medical problems?

A. Medical electronics

B. Genetics electronics

C. Biomedical engineering

D. Biomedical electronics

58. Which device exhibits negative resistance region?

A. Diac

B. Triac

C. Transistor

D. UJT

59. The UJT operates in what region after peak point?

A. Cut off

B. Negative resistance

C. Saturation

D. Positive resistance

60. SCR is a rectifier constructed of silicon material. Silicon is chosen because

A. it is the most abundant material

B. of its strength and ruggedness

C. it is much cheaper than any other material

D. of its high temperature and power capabilities

61. A transduction principle used primarily in optical sensors.

A. Photoconductive transduction

B. Photovoltaic transduction

C. Electromagnetic transduction

D. Piezoelectric transduction

62. What is a solid state equivalent of a gas filled triode?

A. Triac

B. Thyristor

C. SCR

D. SCS

63. The supply voltage is generally ________ that of breakover voltage in an SCR.

A. equal to

B. less than

C. greater than

D. twice

64. The triac is fundamentally a/an _________ with a gate terminal for controlling the turn-on conditions of the bilateral device in either direction.

A. SCR

B. Quadric

C. Shockley diode

D. Diac

65. When the supply voltage exceeds the breakover voltage of an SCR, it

A. starts conducting

B. stops conducting

C. conducts leakage current

D. conducts terminal current

66. The step response of a first order systems is given by

A. y(t) = A0

B. y(t) = A0 + A1es1t + A2es2t +A3es3t

C. y(t) = A0 + A1es1t + A2es2t

D. y(t) = A0 + A1es1t

67. A feedback control system in which the controlled variable is mechanical position.

A. Closed-loop feedback control system

B. Open-loop feedback control system

C. Servomechanism

D. Mechanical servomechanism

68. What is that voltage above when the SCR enters the conduction region?

A. Reverse breakover voltage

B. Forward breakover voltage

C. Holding voltage

D. Trigger voltage

69. A locus or path of the roots traced out on the s-plane as a parameter is changed.

A. Root locus

B. Hyperbola

C. Parabola

D. Circle

70. A control system in which the output is related to the input by device parameters only.

A. Open-loop control system

B. Closed-loop control system

C. Servomechanism

D. Feedback control system

71. What is that value of current below which the SCR switches from the conduction state to the forward blocking region under stated conditions?

A. Holding current

B. Forward current

C. Reverse current

D. Trigger current

72. Which is equivalent to a zener or avalanche region of the fundamental two-layer semiconductor diode?

A. Reverse breakdown voltage

B. Forward breakdown voltage

C. Breakdown voltage

D. Breakover voltage

73. What is the required gate triggering current of GTO?

A. 20 mA

B. 10 mA

C. 30 mA

D. 40 mA

74. What is an automatic speed control device using the centrifugal force on rotating flyweights as the feedback element?

A. Regulator

B. Flywheel governor

C. Field control

D. Throttle valve

75. What is the sensing element of acceleration transducer?

A. Damper

B. Spring

C. Seismic mass

D. Crystal

76. What are some areas where GTO is applicable?

A. Counters

B. Pulse generators

C. Multivibrators

D. All of the above

77. What Greek word which means “switch”?

A. Ristor

B. Trans

C. Thy

D. Thyristor

78. What is the typical turn-on time of an SCR?

A. 1 μs

B. 5 μs

C. 10 μs

D. 3 μs

79. An SCR is a solid state equivalent of which tube?

A. Triode

B. Gas-filled triode

C. Pentode

D. Tetrode

80. The gate of an SCR is ________ with respect to its cathode.

A. positive

B. at zero potential

C. negative

D. at infinite potential

81. A normally operated SCR has an anode which is ________ with respect to cathode.

A. negative

B. positive

C. at zero potential

D. at infinite potential

82. What device measures humidity directly with a single sensing element?

A. Hygrometer

B. Tachometer

C. Venturi meter

D. Hydrometer

83. What is one of the most widely used sensing elements particularly for pressure ranges higher than 2 MPa?

A. Bellows

B. Bourdon tube

C. Capsule

D. Straight tube

84. Which of the following can change the angle of conduction in SCR?

A. Changing anode voltage

B. Changing gate voltage

C. Reverse biasing the gate

D. Changing cathode voltage

85. An SCR is a member of what family?

A. Thyrector

B. Thyratron

C. Thyristor

D. Transistor

86. How many pn junction does SCRs have?

A. Two

B. Four

C. Three

D. Five

87. Which of the following is NOT a method primarily used for density sensing?

A. Sonic

B. Radiations

C. Vibrating element

D. Differential

88. When SCR starts conducting, then _________ losses all control.

A. gate

B. anode

C. cathode

D. anode supply

89. An SCR when turned on has a typical voltage across of

A. zero

B. 0.1 V

C. infinite

D. 1 V

90. The typical turn-off time of an SCR is about

A. 20 to 40 μs

B. 5 to 40 μs

C. 1 to 5 μs

D. 15 to 25 μs

91. An SCR is made of what material?

A. Silicon

B. Carbon

C. Germanium

D. Gallium-arsenide

92. ECG stands for electrocardiography while EEG stands for?

A. electroextracellugraphy

B. electroemyography

C. electroencephalography

D. electrovectorcardiography

93. Acceleration transducers are also called

A. gyros

B. force transducers

C. tachometers

D. accelerometers

94. When an SCR is combined to a switch, it is considered as a _______ switch.

A. bidirectional

B. mechanical

C. unidirectional

D. omnidirectional

95. When the firing angle of SCR is increased, its output

A. decreases

B. increases

C. remains unchanged

D. doubles

96. When the SCR is OFF, the current in the circuit is

A. exactly zero

B. large leakage current

C. small leakage current

D. thermal current

97. The SCR can exercise control over ________ of ac supply.

A. positive or negative half-cycle

B. both positive and negative half-cycles

C. only positive half-cycle

D. only negative half-cycle

98. What is the most widely used altitude and altitude-rate transducers?

A. Flowmeter

B. Psychometer

C. Gyro

D. Gygrometer

99. What sensing element is typically made from a thin-walled tube formed into deep convolutions and sealed at one end, whose displacement can then be made to act on a transduction element?

A. Diaphragm

B. Bellow

C. Capsule

D. Bourdon tube

100. The voltage across an SCR when it is turned on is about

A.0.5 V

B. 0.1 V

C. 1 V

D. 5 V

Questions and Answers in Electronic Systems and Design

Following is the list of multiple choice questions in this brand new series:

Complete List of MCQ in Electronics Engineering per topic