1. Consider the following statements :
The output of a liner circuit, driven with a sine wave at a frequency f, is itself a sine wave
1. at the same frequency
2. with chance of changed amplitude
3. with chances of changed amplitude and phase
Which of the above statements is/are correct ?
a) 1 and 2
b) 1 only
c) 1 and 3
d) 2 only
Ans:- c) 1 and 3
2.Consider the following statements :
The main contribution to photo conduction is by
1. the generation of electron and hole pair by a photon
2. a donor electron jumping into the conduction band because of a photon’s energy
3. a valence electron jumping into an acceptor atate because of a photon’s energy
Which of the above statements is/are correct?
a) 1 only
b) 2 only
c) 3 only
d) 1, 2 and 3
Ans:- a) 1 only
3. Thermal runaway is not possible in FET because as the temperature of the FET increases
a) mobility decreases
b) trans-conductance increases
c) drain current increases
d) trahs-conductance decreases
Ans:- a) mobility decreases
4.A signal may have frequency components which lie in the range of 0.001 Hz to 10 Hz. Which one of the following types of couplings should be chosen in a multistage amplifier designed to amplify the signal ?
a) Capacitor coupling
b) Direct coupling
c) Transformer coupling
d) Double-tuned transformer coupling
Ans:- b) Direct coupling
5. If an input impcdance of op-amp is finitc, then which one of the following statements related to virtual ground is correct ?
a) Virtual ground condition may exist.
b) Virtual ground condition cannot exist.
c) In case of op-amp, virtual ground condition always exists.
d) Cannot make a valid declaration.
Ans:- b) Virtual ground condition cannot exist.
6. Hysteresis is desirable in a Schmitt trigger because
a) energy is to be stored/discharged in parasitic cpacitances
b) effects of temperature variations would be compensated
c) devices in the circuit should be allowed time for sturation and de-saturation
d) it would prevent noise from causing false triggering
Ans:- c) devices in the circuit should be allowed time for sturation and de-saturation
7.In a photoconductive cell, the resistance of the semiconductor material varies with intensity of incident light
a) directly
b) invcrscly
c) exponentially
d) logarithmically
Ans:- b) invcrscly
8.In graded index multimode optical fiber, the refractive index of the core is
a) uniform across its radial distance, except for the cladding
b) maximum at the fiber axis and decreases stepwise towards the cladding
c) maximum at the fiber axis and decreases gradually towards the cladding
d) maximum at the fiber axis and increases stepwise towards the cladding
Ans:- c) maximum at the fiber axis and decreases gradually towards the cladding
9.Consider the following factors:
1. Number of turns of the coil
2. Length of the coil
3. Area of cross-section of the coil
4. Permeability of the core
On which of the above factor does inductance depend?
a) 1, 2 and 3 only
b) 1, 3 and 4 only
c) 1, 2, 3 and 4
d) 2 and 4 only
Ans:- c) 1, 2, 3 and 4
10. A mathematical expression for 50Hz sinusoidal voltage of peak value 80 V will be
a) v = 50 sin 314t
b) v = 50 sin 80t
c) v = 80 sin 314t
d) v = 80 sin 50t
Ans:- c) v = 80 sin 314t
11.Consider the following statements :
1. Fleming’s rule is used where induced e.m.f. is due to flux cutting.
2. Lenz’s law is used when the induced e.m.f. is due to change in flux linkages.
3. Lenz’s law is a direct consequence of the law of conservation of energy.
Which of the above statements are correct ?
a) 1 and 2 only
b) 1 and 3 only
c) 2 and 3 only
d) 1, 2 and 3
Ans:- d) 1, 2 and 3
12. The slip of a 400 V, 3-phase, 4-pole, 50 Hz machine running at 1440 r.p.m. is
a) 6%
b) 5%
c) 4%
d) 3%
Ans:- c) 4%
13.A 500 HP, 440 V, 3-phase, 50 Hz induction motor runs at 950 r.m.p when on full load with a synchronous speed of 1000 r.p.m. For this condition, the frequency of the rotor current will be
a) 4.0 Hz
b) 3.5 Hz
c) 2.5 Hz
d) 2.0 Hz
Ans:- c) 2.5 Hz
14. By adding resistance in the rotor circuit of a slip ring induction motor, the starting current
a) as well as torque reduce
b) as well as torque increase
c) reduces but the starting torque increases
d) increases but the starting torque decreases
Ans:- c) reduces but the starting torque increases
15.Consider the following statements with regards to an induction motor :
1. Maximum torque is independent of rotor resistance.
2. starting torque is maximum when rotor resistance equal rotor reactance
3. Torque is very sensitive to any changes in supply voltage.
Which of the above statements are correct ?
a) 1 and 2 only
b) 1 and 3 only
c) 2 and 3 only
d) 1, 2 and 3
Ans:- d) 1, 2 and 3
16. A transformer has 2% resistance and 5% reactance. what is its voltage regulation at full load with 0.8 p.f. lagging?
a) 5.3%
b) 4.6%
c) 0.53%
d) 0.46%
Ans:- b) 4.6%
17.The ‘residual resistivity’ of a metal is
a) due to lattice vibrations at high temperature
b) due to photon scattering at high temperature
c) temperature-dependant
d) temperature-independent
Ans:- d) temperature-independent
18.Electrical conductivity, thermal conductivity and magnetic properties of ceramic material are
a) very high all the time
b) very low all the time
c) dependent on the meterial
d) ascertainable, instance to instance
Ans:- c) dependent on the meterial
19.Laminated insulation, coated with varnish, is a staple adoption in transformaer assemblage in order to
a) reduce the reluctance of the magnetic path
b) Minimize losses due to eddy currents
c) increase the reluctance of the magnetic path
d) increase the effect of eddy current
Ans:- b) Minimize losses due to eddy currents
20. when a ferromagnetic substance is magnetized there are marginal diminutions in its liner dimensions. This phenomenon is called
a) hysteresis
b) magnetostriction
c) diamagnetism
d) dipolar relaxation
Ans:- b) magnetostriction
21.When the working temperature becomes more than the Curie temperature, a ferromagnetic material becomes a
a) diamagnetic material
b) paramagnetic material
c) ferromagnetic material
d) Mu-material
Ans:- b) paramagnetic material
22.Compared to other materials, a, material with a wider hysteresis loop has
a) lower permeability, higher retentivity and higher coercivity
b) higher permeability, lower retentivity and higher coercivity
c) lower permeability, lower retentivity and lower reluctance
d) lower permeability, lower retentivity and lower residual magnetism
Ans:- a) lower permeability, higher retentivity and higher coercivity
23. Which of the following materials is used in light-emitting diodes?
a) Gallium arsenide sulphate
b) gallium arsenide phosphide
c) Gallium chromate phosphide
d) gallium phosphide sulphate
Ans:- b) gallium arsenide phosphide
24. Consider the following methods in nanoparticle synthesis :
1. Bottom-up
2. Top-down
3. Side-by-side
Which of these methode is /are slow and does/do not conduce to large-scale production?
a) 1 only
b) 2 only
c) 3 only
d) 1, 2 and 3
Ans:- b) 2 only
25.Consider the following statements :
1. Type-I superconductors undergo abrupt transition to the normal state above a critical magnetic field.
2. Type-II superconductors are highly technology useful superconductors because the incidence of a second critical field in them is useful in the preparetion of high field electromagnets.
Which of the above statements is/are correct?
a) 1 only
b) 2 only
c) Both 1 and 2
d) Neither 1 nor 2
Ans:- c) Both 1 and 2
26.Consider the following statements :
1. Metal conductors have more R at higher temperatures.
2. Tungsten can be used as a resistance wire.
3. A superconductive material is one which has practically zero resistance.
Which of the above statements are correct ?
a) 1 and 2 only
b) 1 and 3 only
c) 2 and 3 only
d) 1, 2 and 3
Ans:- d) 1, 2 and 3
27.Consider the following statements regaarding precision in measurements of a quantuity :
1. Precision is the measure of the spread of the incident errors.
2. Precision is independent of the realizable correctness of the measurement.
3. Precision is usually described in terms of number of digits. used in the measurement by a digital instrument.
Which of the above statements are correct?
a) 1, 2 and 3
b) 1 and 2 only
c) 1 and 3 only
d) 2 and 3 only
Ans:- a) 1, 2 and 3
28.Consider the following statements in connection with deflection-type and null-type instruments :
1. Null-type instruments are more accurate than the deflection-type ones.
2. Null-type of instrument can be highly sensitive compared to a deflection-type instrument.
3. Under dynamic conditions, null-type instruments are less preferred to deflection-type instruments.
4. Esponse is faster in null-type instruments as compared to deflection-type instruments.
Which of the above statements are correct ?
a) 1, 2 and 3
b) 1, 2 and 4
c) 1, 3 and 4
d) 2, 3 and 4
Ans:-
a) 1, 2 and 3
29.Consider the following statements :
Sphere gap method of voltage measurement is used
1. for measuring r.m.s. value of a high voltage
2. for-measuring peak value of a hgh voltage
3. as the standard for calibration purposes
Which of the above statements are correct?
a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2 and 3
Ans:- b) 2 and 3 only
30. High frequency (in the MIIz range) and low amplitude (in the mV range) signals are best measured using
a) VTVM with high impedance probe
b) CRO
c) moving-iron instrument
d) digital multimeter
Ans:- b) CRO
31. In scintillation coating applications, shields of which material are generally placed around the photomultiplier tube to overcome interference effects of electrons deflected from their normal path?
a) Ferromagnetic
b) Mu-metal magnetic
c) Electromagnetic
d) Dielectric
Ans:- b) Mu-metal magnetic
32. Which of the following are measured by using a vector voltmeter?
1. Amplifier gain and phase shift
2. Filler transfer function
3. Complex insertion loss
Select the correct answer using the code given below.
a) 1 and 2 only
b) 1 and 3 only
c) 2 and 3 only
d) 1, 2 and 3
Ans:- d) 1, 2 and 3
33.The simplest and most common method of reducing any ‘effect of inductive coupling’ between measurement and power circuits is achieved by using
a) a screen around the entire measurement circuit
b) twisted pairs of cable
c) capacitor(s) to be connected at the power circuit
d) capaacitor(s) to be connected at the measurement circuit
Ans:- b) twisted pairs of cable
34.Consider the following statements regarding Time-Division Multiplexing (TDM) :
1. The information from different measuring points is transmitted serially on the same communication channel.
2. It involves transmission of data samples rather than continuous data trnsmission.
3. It is especially usefull when telemetering fast-changing, high bandwidth data.
Which of the above statements are valid in respect to TDM?
a) 1, 2 and 3
b) 1 and 3 only
c) 1 and 2 only
d) 2 and 3 only
Ans:- c) 1 and 2 only
35.Consider the following regarding essential functional operations of a digital data acquisition system :
1. Handling of analog signals
2. Converting the data to digital form and handing it
3. Making the measurement
4. Internal Programming and telemetry
Which of the above are valid in the stated context?
a) 1, 2, 3 and 4
b) 1, 3 and 4 only
c) 1, 2 and 3 only
d) 2 and 4 only
Ans:- c) 1, 2 and 3 only
36.A network in which all the elements are physically scparable is called a
a) distributed network
b) lumped network
c) passive network
d) reactive network
Ans:- b) lumped network
37. Three identical impedances are first connected in delta across a 3-phase balanced supply. If the same impedances are now connected in star across the same supply, then
a) the phase current will be one-third
b) the line current will be one-third
c) the power consumed will be one-third
d) the power consumed will be halved
Ans:- c) the power consumed will be one-third
38. Consider the following statements regarding trees :
1. A tree contains all the nodes of the graph.
2. A tree shaall contain any one of the loops.
3. Every connected graph has at least one tree.
Which of the above statements are correct?
a) 1 and 2 only
b) 1 and 3 only
c) 2 and 3 only
d) 1, 2 and 3
Ans:- b) 1 and 3 only
39.Consider the following statements with respect to a parlles R-L-C circuit :
1. The bandwidth of the circuit decreases if R is increased.
2. The bandwidth of the circuit remains same if L is increased.
3. At resonance, input impedance is a real quantity.
4. At resonance, the magnitude of the input impedance attains its minimum value
which of the above statements are correct?
a) 1, 2 and 4
b) 1, 3 and 4
c) 2, 3 and 4
d) 1, 2 and 3
Ans:- d) 1, 2 and 3
40. One of the basic characteristics of any steady-state sinnusoidal response of a liner R-L-C circuit with constant R,L and C value is
a) the output remains sinusoidal with its frequency being the same as that of the source
b) the output remains sinusoidal with its frequency differing from that of the souece
c) the output amplitude equals the source amplitude
d) the phase amgle difference between the source and the output is always zero
Ans:- a) the output remains sinusoidal with its frequency being the same as that of the source
41. Which one of the following Analog-to-Digital converters (ADC) does not use a DAC ?
a) Digital ramp ADC
b) Successive approximation ADC
c) Single-slope ADC
d) Counting ADC
Ans:- c) Single-slope ADC
42.A 12-bit A/D converter has a full-scale analog input of 5 V. its resolution is
a) 1.22 mV
b) 2.44 mV
c) 3.66 mV
d) 1.88 mV
Ans:- a) 1.22 mV
43.Which of the following circuits converts/convert a binary number on the input to a one-hot encoding at the output?
1. 3-to-8 binary decoder
2. 8-to-3 decoder
3. Comparator
Select the correct answer using the code given below.
a) 1 only
b) 2 only
c) 3 only
d) 1, 2 and 3
Ans:- a) 1 only
44.How many 3-to-8 line decoders with an enabler input are needed to construct a 6-to-64 line decoder without using any other logic gates?
a) 11
b) 10
c) 9
d) 8
Ans:- c) 9
45.The output of a NOR gate is
a) high if all of its inputs are high
b) low is all of its inputs are low
c) high if all of its inputs are low
d) high if only one of its inputs is low
Ans:- c) high if all of its inputs are low
46.If the input to a T flip-flop is a 100 MHz signal, the final output of three T flip- flops in a cascade is
a) 1000 MHz
b) 520 MHz
c) 333 MHz
d) 12.5 MHz
Ans:- d) 12.5 MHz
47.A dominant pole is determined as
a) the highest frequency pole among all poles
b) the lowest frequency pole at least two octaves lower than other poles
c) the lowest frequency pole among all poles
d) the highest frequency pole at least two octaves higher than other poles
Ans:- b) the lowest frequency pole at least two octaves lower than other poles
48. the modulation scheme used in GSM is
a) frequency shift keying
b) phase shift keying
c) Gaussian minimum shift keying
d) amplitude shift keying
Ans:- c) Gaussian minimum shift keying
49.The largest error between reference input and output during the transfer period is called
a) peak error
b) transient overshoot
c) peak overshoot
d) transient deviation
Ans:- c) peak overshoot
50.A 32 kB RAM is formed by 16 numbers of a particular type of SRAM IC. If each IC needs 14 address bits, what is the IC capacity?
a) 32 kbits
b) 16 kbits
c) 8 kbits
d) 4 kbits
Ans:- b) 16 kbits