| Post Name | Lecturer in Electronics and Instrumentation (Polytechnics) - Technical Education Department |
|---|---|
| Question Paper Code | 121/2023/OL |
| Category Code | 146/2022 |
| Date of Test | 24 July 2023 |
| Exam Type | Online Examination |
| Total Questions | 100 |
1
Let A, P and Q be invertible square matrices with Q = P⁻¹AP. Then Aⁿ is
Answer
C. PQⁿP⁻¹
2
Let A = [[1, −1, 2], [3, 2, −4], [−2, 2, −4]]. Det(A) denotes the determinant of A. Then Det(A⁵) =
Answer
B. 0
3
If P and Q are the coefficients of xⁿ in the expansion of (1 + x)²ⁿ and (1 + 1)²ⁿ⁻¹, respectively, then P/Q is:
Answer
Question Cancelled
4
A,B, 45° are the angles in a triangle such that Cot A+ Cot B + Cot 45° = CotA CotB Cot 45°. Then tan(A+B) is
Answer
C. -1
5
The solution of the system of equations x + y + z = 6, y + 3z = 11 and x − 2y + z = 0 is:
Answer
B. x=1, y=2, z=3
6
Equation of the line passing through the point of intersection of the lines 2x+3y-1=0, 3x+4y-6=0 and parallel to 5x+4y-2=0
Answer
D. 5x+4y-34=0
7
Which of the following are the solutions of the equation sin x = −√3/2?
Answer
D. nπ + (−1)ⁿ4π/3
8
The tangent of the curve is parallel to the line at the point (a,b). Then the point (a,b)
Answer
C. (1,1)
9
∫[(e²ᵗ + 1)/(2²ᵗ − 1)] dt is
Answer
Question Cancelled
10
Area lying above the line y = 0 of the circle x² + y² = a² bounded between x = −a and x = a is
Answer
A. πa²/2
11
The maximum water absorption in percentage for class 25 brick is
Answer
B. 15
12
Indian Standard code for requirements of Ordinary portland cement is
Answer
A. IS 269:2015
13
Minimum Cover to reinforcement of footing shall be
Answer
B. 50 mm
14
The whole circle bearing of a line is 300 degrees. Its reduced bearing is
Answer
D. N60° W
15
The sensitivity of a bubble tube can be increased by
Answer
C. Both 1 and 2 above
16
In SI engines, the power and economy are altered by adjusting
Answer
B. Rate of air flow
17
The piston head of a two stroke engine has a deflector to ensure
Answer
A. Charge delivery is directed upward into the cylinder
18
The combustion duration of a CI engine when compared to a SI engine is
Answer
B. More
19
To adjust for the change in length of propeller shaft while the vehicle is in motion
Answer
B. A slip joint is provided
20
The most common economizers used in thermal power plants to prevent corrosion of the flue gas passages are
Answer
C. Non condensing type
21
A capacitor when connected across a dc voltage source accumulates a charge of Q coulombs . When two such capacitors are connected in series across the same voltage source, the total accumulated charge will be
Answer
C. Q/2
22
Two resistances of value 10 ohms and 15 ohms are connected in parallel and included in a dc circuit. The 10 ohms resistance carries 3 amperes. The what will be the current carried by the 15 ohm resistor?
Answer
A. 2 A
23
What type of generator will be selected for producing a dc power supply that will have nearly constant voltage from no load to full load?
Answer
D. Cumulative compound generator
24
A three phase balanced load draws 0.5 A line current from 400 V supply at a power factor of 0.5. What is the energy consumed by this load when it is connected to the supply for 10 hours?
Answer
B. 1.732 kWh
25
A thyrite type lighting arrester is used to
Answer
C. bypass surge to the ground
26
LED is made up of
Answer
B. GaAs
27
The ripple factor of full wave bridge rectifier is
Answer
C. 0.48
28
1C 7805 is used for
Answer
D. 5V
29
Codes used for spreading in CDMA system is
Answer
A. Orthogonal
30
Which wireless mobile technology is used for image transmission?
Answer
Question Cancelled
31
A resistance temperature detector (RTD) has a resistance of 10Ω at 0°C. When measuring the temperature of a process, a resistance value of 15Ω is recorded. calculate the temperature corresponding to this resistance value. Assume that the sensing element used in the RTD has a temperature coefficient of resistance of 0.001/°C
Answer
A. 500°C
32
Which type of radiation is typically used in the radiation absorption method for level measurement?
Answer
C. Gamma rays
33
Calculate the Reynold's number of a fluid of viscosity 0.5 Pascal- second and density of 500Kg/ flowing in a horizontal circular tube of diameter 50 cm with a flow speed of 2.5m/s
Answer
C. 1250
34
Ultrasonic level gauges operate based on the principle of
Answer
B. Reflection
35
Which of the following is/are the assumptions(s) on the flow of fluid in Bernoulli's equation
Answer
D. All of the above
36
A given substance has a specific gravity of 5. Calculate its density in Kg/
Answer
D. 5000
37
Which of the following is an example of an orifice viscometer?
Answer
A. Saybolt's viscometer
38
Match the following quantities in Column I with their units in column II Column I Column II (a) Humidity (i) Ns/ (b) Torque (ii) g/ (c) Pressure (iii) N/ (d) Viscosity (iv) Nm
Answer
C. (a)-(ii), (b)-(iv), (c)-(iii), (d)-(i)
39
A chromel-alumel thermocouple generates an e.m.f. of 10 mV. Determine the temperature of the hot junction of the cold junction is at a temperature of 15°C and the sensitivity if the thermocouple is 0.04 mV/°C
Answer
B. 265°C
40
Which of the following manometric fluids should be used to determine the pressure difference between two horizontal pipes, through which water is flowing, using an inverted manometer?
Answer
B. Manometric fluid with a specific gravity of 0.7
41
Two pipes, each of diameter d1, converge to form a pipe of diameter d2. What should be the relation between d1 and d2 such that the velocity in the pipe with diameter d2 becomes double of that in each of the pipes with diameter d1?
Answer
A. d1=d2
42
The working principle of a Pirani gauge is based on
Answer
A. Thermal conductivity
43
The Bourdon-type pressure gauge operates based on the principle of
Answer
C. Elastic deformation
44
A McLeod gauge is commonly used to measure
Answer
B. Pressure
45
A thermistor has temperature coefficient of -5% over a temperature range of 25°C to 50°C. If the resistance of thermistor is 120Ω at 25°C, what is the resistance of at 40°C?
Answer
D. 30Ω
46
Which of the following is not the governing principle of variable inductance transducers?
Answer
D. Change of differential inductance
47
As the basic principle of radiation pyrometer, the total thermal energy of the radiation emitted by a black body is proportional to ________ power of the temperature of the hot body
Answer
D. Fourth
48
In the liquid level measuring system with float the force applied on the measuring device is
Answer
C. F=mg-ρghA
49
Differential pressure-based method of specific gravity measurement works based on
Answer
B. Hydrostatic principle
50
Select one of the advantages of turbine flow meter
Answer
A. Good dynamic behavior
51
Which one is not the desirable property of manometric fluid
Answer
C. High-co-efficient of thermal expansion
52
Pirani gauges are useful to measure pressures ranging from
Answer
A. 10 × to 1 torr
53
In vortex shedding flow meter, the constant of proportionality in computing shedding frequency is known as
Answer
C. Strouhal number
54
Consider a venturi flume built in a rectangular channel 1m wide and having a throat width of 0.4m. Assume the upstream head is 0.52m and the measured head in the throat is 0.4m. What is the discharge through the venturi flume?
Answer
A. 0.235 m³/s
55
A venturi of throat diameter 60 mm is placed in a water pipe of diameter 100 mm to measure volumetric flow. 60 × 10⁻³ m³/s is the volumetric flow rate through the tube. Water has a density of 10³ kg/m³ and viscosity of 10⁻³ Ns/m². Determine the Reynolds number.
Answer
B. 1273.8 × 10³
56
The point where the highest differential pressure is obtained in the orifice plate is known as
Answer
C. Vena contracta
57
The measurement of viscosity of a motor oil is done by a Saybolt viscometer. The time recorded for 60ml drainage is 190 s. The kinematic viscosity is
Answer
C. 40.86 × 10⁻⁶ m²/s
58
The point at which the vapor starts to condensate when the mixture is cooled at constant pressure
Answer
B. Dew point
59
A temperature process has the operating range 100 to 500K with the setpoint as 300K. Find the percentage of error span when the temperature is 450K
Answer
B. -37.5
60
Proportional controller introduces ____________ and it can be minimized by reducing _________
Answer
A. Residual error, proportional band
61
A controller outputs 4-20mA current signal to the final control element. Find the current when the controller has a proportional band of 25%
Answer
A. 8 mA
62
The measurement range of an integral control system spans from 0.6 to 1.6 V, and it generates an output voltage of 0 to 9.0 V. Compute the gain G1 of the op amp to implement the integral controller of gain KI = 6% (%-min).
Answer
Question Cancelled
63
In a pneumatic control valve, a force of 320 N is applied to open a valve. Find the diaphragm area, if a control gauge pressure of 50 kPa must provide this force.
Answer
C. 6.4 × 10⁻³ m²
64
An equal percentage valve has a maximum flow of 100 m³/s and a minimum flow of 4 m³/s. If the full travel is 4 cm, find the flow at 2 cm opening.
Answer
D. 20 m³/s
65
Valve positioners are mandatory in the following circumstances (i) When accurate valve position is required (ii) To speed up the response of a valve (iii) Where a pressure boost is required to give the necessary actuator force (iv) All the above
Answer
D. (iv)
66
Which among the following is the tendency of a process to adopt specific value of the controlled variable for nominal load with no control operations?
Answer
B. Self regulation
67
If a single process output is controlled by incorporating the actions of several manipulated variables, which produce the same effect on the overall system is known as
Answer
D. Splitrange control
68
In a feed forward control loop, process transfer function is Gₚ(s) = 9e⁻⁰·⁶ˢ/(s + 1) and disturbance is Gₑ(s) = 3e⁻⁰·³ˢ/(s + 1). Find the transfer function Gᶜ(s) of the feedforward controller.
Answer
A. (1/3)e⁰·³ˢ
69
A PLC ladder logic diagram is shown in Fig. Find the equivalent Boolean logic for the ladder logic
Answer
D. C3 = (X1 OR X2) AND ((NOT C1) OR C2) AND X3
70
In a biological neuron, what type of signal transmission takes place at synapse?
Answer
B. Chemical process
71
For a parameter control device, identify the symbol "PI".
Answer
C. Vacuum indicate
72
According to P and ID, identify the valve type given below
Answer
A. Plug valve
73
Mention the significance of interstage coolers in compressors
Answer
A. To reduce the temperature of the air
74
Name the method which removes water molecule by changing its chemical composition
Answer
B. Dehydration
75
In gears, the locus of a point on the line which rolls out without slipping on the fixed circle is called
Answer
C. Involute profile
76
A pinion gear with 33 teeth has a rotational speed of 1200 rpm and drives a gear at 600 rpm. determine the number of teeth on the gear
Answer
B. 66
77
Which of the following coordinate system can be used for designing an industrial robot?
Answer
D. All the above
78
Which one of the following is not a programming language of a robot?
Answer
B. MARS
79
Which of the following system is a time variant system?
Answer
B. y(n) = x(−n)
80
A mechanical rotational system is represented by J₁(d²θ₁/dt²) + B₁[d(θ₁−θ₂)/dt] + K₁(θ₁−θ₂) = T, where T is torque, θ is angular displacement, J is moment of inertia, B is dashpot coefficient and K is spring stiffness constant. Find the equivalent torque-voltage electrical analogous equation.
Answer
C. L₁(di₁/dt) + R₁(i₁+i₂) + (1/C₁)∫(i₁−i₂)dt = e(t)
81
Consider the following properties of signal flow graph (i) Signal flow graph is applicable to linear systems (ii) Signal flow graph of a system is unique (iii) Signals travel along branches only in the marked direction Which of the above statements is/are incorrect?
Answer
C. (ii) only
82
For the construction of Bode plot, the corner frequencies (rad/sec) for the given transfer function
Answer
D. 0.5 and 0.25
83
Match the following open-loop transfer functions with the types of input signals which give rise to constant steady-state error values. Assume H(s) = 1. (a) G(s) = 10/[s(s + 2)(s + 3)] (b) G(s) = 5(s + 1)/[(s + 1)(s + 2)] (c) G(s) = (s + 1)/[s²(s + 4)(s + 5)] (i) Step (ii) Parabolic (iii) Rsmp
Answer
D. (a)-(iii), (b)-(i), (c)-(ii)
84
Using Routh criterion, determine the stability of the system whose characteristics equation is
Answer
A. Marginally stable
85
If a single phase full converter generates a peak value of 300 V for the conduction angle 45°, then what will be the average output voltage of the converter?
Answer
D. (√2/π) × 300 V
86
Identify the type of chopper from the circuit shown in Fig
Answer
A. Type B chopper
87
Ultra filtration rate in dialysis is due to
Answer
C. Hydrostatic and osmotic transmembrane pressure
88
Which semiconductor laser is typically emit light i the 1200nm to 1550nm region of the spectrum
Answer
A. lnGaAsP
89
How many electrodes are used in the clinical electroencephalography?
Answer
B. 21
90
The radius of trajectory (r) of each charged particle in mass spectrometer depends on
Answer
C. √(2Vm/(h²e))
91
The flow cytometry sensor is used for
Answer
A. Blood count
92
Which Laser is NOT working in continuous wave (cw) mode of operation
Answer
D. Ruby Laser
93
Unipolar chest electrode in ECG is measured with respect to
Answer
D. Right leg(RL)
94
Calculate the magnetic field in Tesla (T) at 2 mm from a wire carrying 10 A of current.
Answer
B. 10 × 10⁻⁴ T
95
Which is help to remove spurious voltage generated during magnet current reversal in electromagnetic flow meter
Answer
A. Gating circuits
96
The blood gas analyzer are measure
Answer
D. pH, pCO2 and pO2
97
To reduce the motion artifacts in the CT scan machine
Answer
C. Scan time less than breath hold time
98
Spatial resolution in NMR imaging system can be improved by reducing
Answer
Question Cancelled
99
Synthetic piezo electric material is
Answer
B. Lead zirconate Titanate
100
Which electrode metal has highest potential between electrodes in electrolyte (Saline)
Answer
C. Silver
Discussion
Ask a doubt or share a tip.
No comments yet — start the discussion.