Download AppGovt. JobsFree G.K. & Current AffairsScholarshipBlog
Free PracticeContact
📚 Exam by Category
▾
Objective Questions

Latest CSIR CGCRI Technical Assistant Exam Question (Objective Questions), MCQ in English

Subjects : Electronics

Question Bank CSIR CGCRI Technician (Paper-III) Exam - English
Back to Exam

Electronics

Question 1Single Answer
At temperature of 298 Kelvin, Silicon is not suitable for most-electronic applications, due to small amount of conductivity. This can be altered by
  1. A
    Gettering
  2. B
    Doping
  3. C
    Squeezing
  4. D
    Sintering
Question 2Single Answer
By doping Germanium with Gallium, the types of semi-conductors formed are
1. N type
2. P type
3. Intrinsic
4. Extrinsic
  1. A
    1 and 4
  2. B
    2 and 4
  3. C
    1 and 3
  4. D
    2 and 3
Question 3Single Answer
An n-type of silicon can be formed by adding impurity of:
1. Phosphorous
2. Arsenic
3. Boron
4. Aluminum 
Which of the above are correct ?
  1. A
    1 and 2
  2. B
    2 and 3
  3. C
    3 and 4
  4. D
    1 and 4
Question 4Single Answer
According to Einstein’s relationship for a semiconductor, the ratio of diffusion constant to the mobility of the charge carriers is
  1. A
    Variable and is twice the volt equivalent of the temperature
  2. B
    Constant and is equal to the volt equivalent of the temperature
  3. C
    Equal to two and is twice the volt equivalent of the temperature
  4. D
    Equal to one and is equal to the volt equivalent of the temperature
Question 5Single Answer
Swept-out voltage in PIN diode happens when PIN diode is
  1. A
    Forward biased and the thickness of the depletion layer decreases till I-region becomes free of mobile carriers
  2. B
    Reverse biased and the thickness of the depletion layer increases till I-region becomes free of mobile carriers
  3. C
    Forward biased and the thickness of the depletion layer increases till I-region becomes free of mobile carriers
  4. D
    Reverse biased and the thickness of the depletion layer decreases till I-region becomes free of mobile carriers
Question 6Single Answer
The number of holes in an N-type silicon with intrinsic value 1.5 × 1010/cm3 and doping concentration of 1017/cm3, by using mass-action law is
  1. A
    6.67 × 106/cc
  2. B
    4.44 × 10-25/cc
  3. C
    1.5× 10-24/cc
  4. D
    2.25 × 103/cc
Question 7Single Answer
A tunnel-diode is best suited for
  1. A
    Very low frequencies
  2. B
    50 Hz
  3. C
    100 Hz
  4. D
    Microwave frequencies
Question 8Single Answer
Small recovery time of a diode is most significant for
  1. A
    Line-frequency rectification
  2. B
    Switching operations
  3. C
    High-frequency rectifications and switching operations
  4. D
    Low-frequency rectifications and switching operations
Question 9Single Answer
In JFET, when operated above the pinch-off voltage, the
  1. A
    Depletion region becomes smaller
  2. B
    Drain current starts decreasing
  3. C
    Drain current remains practically constant
  4. D
    Drain current increases steeply
Question 10Single Answer
Thermal runaway is not possible in FET because, as the temperature of FET increases
  1. A
    The drain current increases
  2. B
    The mobility of charge carriers decreases
  3. C
    The mobility of charge carriers increases
  4. D
    The transconductance increases
Question 11Single Answer
Consider the following statements regarding an N-P-N Bipolar Junction Transistor:
1. Emitter diode is forward biased and collector diode is reverse biased
2. Emitter has many free electrons
3. Free electrons are injected into base and pass through collector
4. Depletion layers around junction J1 and J2 of BJT are widened 
    Which of the above statements are correct?
  1. A
    1, 2 and 4
  2. B
    1, 3 and 4
  3. C
    2, 3 and 4
  4. D
    1, 2 and 3
Question 12Single Answer
A freewheeling diode T phase controlled rectifier
  1. A
    Improves the line power factor
  2. B
    Enables inverse operation
  3. C
    Is responsible for additional reactive power
  4. D
    Is responsible for additional harmonics
Question 13Single Answer
The zeners incorporated within the encapsulations of some MOSFETs are meant for
  1. A
    Reducing the cost
  2. B
    Biasing the gate circuit
  3. C
    Self-protecting the device against transients
  4. D
    None of the above
Question 14Single Answer
When UJT is used for triggering an SCR, the wave-shape of the signal obtained from UJT circuit is
  1. A
    Sine wave
  2. B
    Saw tooth wave
  3. C
    Trapezoidal wave
  4. D
    Square wave
Question 15Single Answer
Darlington pairs are frequently used in linear ICs because, they
  1. A
    Do not require any capacitors or inductors
  2. B
    Have enormous impedance transformation capability
  3. C
    Can be readily formed/hooked from two adjacent transistors
  4. D
    Resemble emitter follower
Question 16Single Answer
In a MOS capacitance fabricate on a P-type semiconductor, strong inversion occurs, when potential is
  1. A
    Equal to Fermi level
  2. B
    Zero
  3. C
    Negative and equal to Fermi potential in magnitude
  4. D
    Positive and equal to Fermi potential in magnitude
Question 17Single Answer
A CMOS amplifier when compared to an N channel MOSFET has the advantage of
  1. A
    Higher cutoff frequency
  2. B
    Higher voltage gain
  3. C
    Higher current gain
  4. D
    Lower power dissipation
Question 18Single Answer
Consider the following statements regardingoptocouplers:
1. Optocouplers are LEDs driving photodiodes in a single package to provide electrical isolation between input and output
2. Optocouplers is LED driving a phototransistor in a single package that replaces pulse transformers working at input zero crossing
3. Optocouplers are used as temporary non fixed joints between optical fibre terminations 
  Which of the above statements are correct?
  1. A
    1, 2 and 3
  2. B
    1 and 2 only
  3. C
    1 and 3 only
  4. D
    2 and 3 only
Question 19Single Answer
Which of the following does not cause permanent damage to an SCR ?
  1. A
    High current
  2. B
    High rate of rise of current
  3. C
    High temperature rise
  4. D
    High rate of rise of voltage
Question 20Single Answer
The basic structure of an avalanche photodiode is
  1. A
    p+ – i – p – n+
  2. B
    p+ – I – n+
  3. C
    p+ – p- – n+
  4. D
    i – p- – n+
Question 21Single Answer
A five digits number is formed using the digits 1, 3, 5, 7 and 9 without repeating any of them. What is the sum of all such possible five digit numbers ?
  1. A
    6666660
  2. B
    6666600
  3. C
    6666666
  4. D
    6666606
Question 22Single Answer
Examples of an active display and a passive display respectively are
  1. A
    LCD and Gas discharge plasma
  2. B
    LED and LCD
  3. C
    Gas discharge plasma and LED
  4. D
    Electrophoretic Image display and LED
Question 23Single Answer
The dc resistivity and permeability exhibited by a type 1 superconductor are respectively
  1. A
    Zero and zero
  2. B
    Zero and unity
  3. C
    Unity and zero
  4. D
    Unity and unity
Question 24Single Answer
Statement (I):One of the mechanisms by which a transistor’s usefulness may be terminated, as the collector voltage is increased, is called punch through.
Statement (II): Punch through results from the increased width of the collector-junction transition region with increased collector-junction voltage
  1. A
    Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
  2. B
    Both Statement (I) and Statement (II) are individually true and Statement (II) is NOT the correct explanation of Statement (I)
  3. C
    Statement (I) is true but Statement (II) is false
  4. D
    Statement (I) is false but Statement (II) is true
Question 25Single Answer
Statement (I): Conduction takes place in an enhancement MOSFET only for gate voltages below the threshold level.
Statement (II):In an enhancement MOSFET, a channel of semiconductor of the same type as the source and drain is induced in the substrate by a positive voltage applied to the gate.
  1. A
    Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
  2. B
    Both Statement (I) and Statement (II) are individually true and Statement (II) is NOT the correct explanation of Statement (I)
  3. C
    Statement (I) is true but Statement (II) is false
  4. D
    Statement (I) is false but Statement (II) is true
Question 26Single Answer
Statement (I): MOSFET is a field effect transistor whose drain current is controlled by the voltage applied at the gate.
Statement (II): MOSFET is an insulated gate FET
  1. A
    Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
  2. B
    Both Statement (I) and Statement (II) are individually true and Statement (II) is NOT the correct explanation of Statement (I)
  3. C
    Statement (I) is true but Statement (II) is false
  4. D
    Statement (I) is false but Statement (II) is true
Question 27Single Answer
Statement (I): All passive components can be fabricated in a single chip.
Statement (II): As opposed to discrete circuits where all components are separately inserted and connected, in an integrated circuit, they are simultaneously created on a chip of semiconductor material during manufacturing
  1. A
    Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
  2. B
    Both Statement (I) and Statement (II) are individually true and Statement (II) is NOT the correct explanation of Statement (I)
  3. C
    Statement (I) is true but Statement (II) is false
  4. D
    Statement (I) is false but Statement (II) is true
Question 28Single Answer
What is an advantage of MOS transistor structure in integrated circuits?
  1. A
    Faster switching
  2. B
    Less capacitance
  3. C
    Higher component density and lower cost
  4. D
    Lower resistance
Question 29Single Answer
An LTI system has a wide-sense stationary (WSS) input signal with zero mean. Its output is
  1. A
    Non-zero mean and non-WSS signal
  2. B
    Zero mean and WSS signal
  3. C
    Non-zero mean and WSS signal
  4. D
    Zero mean and non-WSS signal
Question 30Single Answer
In degenerately doped n conduction n-type semiconductor, the Fermi level lies in conduction band when
  1. A
    Concentration of electrons in the conduction band exceeds the density of states in the valence band
  2. B
    Concentration of electrons in the valence band exceeds the density of states in the conduction band
  3. C
    Concentration of electrons in the conduction band exceeds the product of the density of states in the valence band and conduction band
  4. D
    None of the above
Question 31Single Answer
The purpose of connecting a Zener diode in a UJT circuit, used for triggering thyristors, is to
  1. A
    Expedite the generation of triggering pulses
  2. B
    Delay the generation of triggering pulses
  3. C
    Provide a constant voltage to UJT to prevent erratic firing
  4. D
    Provide a variable voltage to UJT as the source voltage changes
Question 32Single Answer
Statement (I):With a small additional energy, usually thermal, the valence electrons in germanium can become free electrons.
Statement (II):The valence electrons in germanium are in the fourth orbit and are at high energy level.
  1. A
    Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
  2. B
    Both Statement (I) and Statement (II) are individually true and Statement (II) is not the correct explanation of Statement (I)
  3. C
    Statement (I) is true but Statement (II) is false
  4. D
    Statement (I) is false but Statement (II) is true
Question 33Single Answer
Statement (I): An FET is a current-controlled device.
Statement (II): Operation of an FET depends only on majority.
  1. A
    Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
  2. B
    Both Statement (I) and Statement (II) are individually true and Statement (II) is not the correct explanation of Statement (I)
  3. C
    Statement (I) is true but Statement (II) is false
  4. D
    Statement (I) is false but Statement (II) is true
Question 34Single Answer
Statement (I): Thermal runaway is not possible in an FET.
Statement (II): As the temperature of an FET increases, the mobility of carriers decreases.
  1. A
    Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
  2. B
    Both Statement (I) and Statement (II) are individually true and Statement (II) is not the correct explanation of Statement (I)
  3. C
    Statement (I) is true but Statement (II) is false
  4. D
    Statement (I) is false but Statement (II) is true
Question 35Single Answer
Statement (I): In an enhancement type MOSFET (with n-type source and drain regions), only positive voltage can be applied to the gate with respect to the substrate (p-type).
Statement (II): Only with a positive voltage to the gate, an ‘inversion layer’ is formed and conduction can take place
  1. A
    Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
  2. B
    Both Statement (I) and Statement (II) are individually true and Statement (II) is not the correct explanation of Statement (I)
  3. C
    Statement (I) is true but Statement (II) is false
  4. D
    Statement (I) is false but Statement (II) is true
Question 36Single Answer
For a fully transposed transmission line         
  1. A
    positive negative and zero sequence impedances are equal
  2. B
    positive and negative sequence impedances are equal
  3. C
    zero and positive sequence impedances are equal  
  4. D
    negative and zero sequence impedances are equal                             
Question 37Single Answer
The best device for improving the switching speeds of bipolar transistors is
  1. A
    Speed-up capacitor
  2. B
    Transistor with higher cut-off frequency
  3. C
    Clamping diode
  4. D
    Clamping diode with zero storage time
Question 38Single Answer
The early effect in bipolar junction transistor is caused by
  1. A
    Fast turn-off
  2. B
    Fast turn-on
  3. C
    Large emitter to base forward bias
  4. D
    Large collector to base reverse bias 
Question 39Single Answer
To get higher cut-off frequency in a BJT, base sheet resistance should be
  1. A
    Low
  2. B
    High
  3. C
    Equal to cut-off frequency
  4. D
    Zero
Question 40Single Answer
A BJT operates as a switch
  1. A
    In the active region of transfer characteristics
  2. B
    With no signal condition
  3. C
    Under small signal conditions
  4. D
    Under large signal conditions
Question 41Single Answer
What is the biasing condition of junctions in bipolar junction transistor to work as an amplifier?
  1. A
    Reverse biased base to emitter junction and reverse biased base to collector junction
  2. B
    Forward biased base to emitter junction and reverse biased base to collector junction
  3. C
    Forward biased base to emitter junction and forward biased base to collector junction
  4. D
    Reverse biased base to emitter junction and forward biased base to collector junction
Question 42Single Answer
In a JFET, operating above pinch-off voltage, the
  1. A
    Drain current increases steeply
  2. B
    Drain current remains practically constant
  3. C
    Drain current starts decreasing
  4. D
    Depletion region reduces
Question 43Single Answer
If Vcc = 18V, voltage divider resistances R1 = 4.7 kΩ and R2 = 1500 Ω, what is the base bias voltage?
  1. A
    8.70 V
  2. B
    4.35 V
  3. C
    2.90 V
  4. D
    0.70 V
Question 44Single Answer
An SCR has an anode supply of sine voltage 200Vr.m.s., 50 Hz applied through a 100 Ω resistor and fired at an angle of 60°. Assuming no voltage drop, the r.m.s. value of the output voltage is nearly
  1. A
    90 V
  2. B
    126 V
  3. C
    166 V
  4. D
    200 V
Question 45Single Answer
In a GTO, anode current begins to fall when gate current
  1. A
    Is negative peak at time t=0
  2. B
    Is negative peak at time t=storage period
  3. C
    Just begins to become negative at t=0
  4. D
    Just begins to become positive at t=0 
Question 46Single Answer
An SCR is turned off when its turn-off time is
  1. A
    less than the circuit time constant
  2. B
    greater than the circuit time constant
  3. C
    less than the circuit turn-off timex
  4. D
    greater than the circuit turn-off time
Question 47Single Answer
The bandwidth of a digitally recorded signal primarily depends upon
  1. A
    The physical properties of the system components processing the signal
  2. B
    The frequency at which the signal is sampled
  3. C
    The frequency of the clock signal that is used to encode binary values responding the signal
  4. D
    The frequency of the noise affecting signal quality
Question 48Single Answer
While measuring the voltage developed by a thermocouple, it is found that there is always an offset voltage. This is due to
  1. A
    A voltage across thermocouple even at very low temperature
  2. B
    Some photoelectric voltage across the junction due to ambient light
  3. C
    A barrier potential across the junction
  4. D
    An additional thermocouple is formed due to the connecting wires and one of the metals.
Question 49Single Answer
For an antenna, radiation intensity is defined as
  1. A
    The time-averaged radiated power per unit solid angle
  2. B
    The peak radiated power per unit solid angle
  3. C
    The peak radiated power per unit area
  4. D
    The time-averaged radiated power per unit area
Question 50Single Answer
A source of (power/energy) feeds the input port of an amplifier and the output port is connected to a ‘load’. The input impedance of the ideal amplifier should ideally be
  1. A
    Zero
  2. B
    ∞
  3. C
    Low
  4. D
    high
Important Questions Package

CSIR CGCRI Technical Assistant Exam Online Question Bank Package

Buy CSIR CGCRI Technical Assistant Important Questions, MCQ, question answer in Hindi & English. It will help you to score high marks in CSIR CGCRI Technical Assistant question bank 2026 in Online, PDF & Print study material.

+ Free Monthly Current Affairs, GK & more PDF Download
Sr.Package NameAmount
1.CSIR CGCRI Technical Assistant / Technician (Paper-I) Exam - Hindi
Description : 1000 Question with Answer.
₹101 [₹500]
2.CSIR CGCRI Technical Assistant / Technician (Paper-I) Exam - Hindi
Description : 2000 Question with Answer.
₹151 [₹500]
3.CSIR CGCRI Technical Assistant / Technician (Paper-I) Exam - English
Description : 1000 Question with Answer.
₹101 [₹500]
4.CSIR CGCRI Technical Assistant / Technician (Paper-I) Exam - English
Description : 2000 Question with Answer.
₹151 [₹500]
5.CSIR CGCRI Technical Assistant / Technician (Paper-II) Exam - Hindi
Description : 1000 Question with Answer.
₹101 [₹500]
6.CSIR CGCRI Technical Assistant / Technician (Paper-II) Exam - Hindi
Description : 2000 Question with Answer.
₹151 [₹500]
7.CSIR CGCRI Technical Assistant / Technician (Paper-II) Exam - English
Description : 1000 Question with Answer.
₹101 [₹500]
8.CSIR CGCRI Technical Assistant / Technician (Paper-II) Exam - English
Description : 2000 Question with Answer.
₹151 [₹500]
9.CSIR CGCRI Technical Assistant / Technician (Paper-III) Exam - Hindi
Description : 1200 Question with Answer.
₹101 [₹500]
10.CSIR CGCRI Technical Assistant / Technician (Paper-III) Exam - English
Description : 1140 Question with Answer.
₹101 [₹500]
View More Questions
Back to Exam