Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

In a second order under damped system, the

A. time required for the response of first reach its ultimate value is called the response time.
B. overshoot (which is a measure of how much the response exceeds the ultimate value) increase with the decrease of damping co-efficient e.
C. decay ratio (which is the ratio of the sizes of successive peaks) is equal to the reciprocal of overshoot.
D. characteristics of a step response is represented by
Answer» C. decay ratio (which is the ratio of the sizes of successive peaks) is equal to the reciprocal of overshoot.
2.

When a bare thermocouple is covered by a protective sheath, the response becomes

A. faster and oscillatory.
B. faster and non-oscillatory.
C. slower and oscillatory.
D. slower and non-oscillatory.
Answer» E.
3.

Working principle of disappearing filament type optical pyrometer is based on the

A. Wien's law
B. Seebeck effect
C. Kirchoff's law
D. Peltier effect
Answer» B. Seebeck effect
4.

In a single tank system, the transfer function of __________ to inlet flow rate is 1/TS+1.

A. outlet flow rate
B. level
C. both (a) & (b)
D. neither (a) nor (b)
Answer» B. level
5.

Which of the following thermocouples is capable of measuring a temperature of -50°C?$

A. Platinum - platinum + rhodium
B. Chromel - alumel
C. Iron-constantan
D. Copper - constantan
Answer» B. Chromel - alumel
6.

__________ controller has the maximum stabilising time.

A. P
B. PD
C. PI
D. PID
Answer» D. PID
7.

Meleoid gauge measures the __________ pressure.

A. positive
B. sub-atmospheric
C. very high
D. atmospheric
Answer» C. very high
8.

An aneroid barometer measures the __________ pressure.

A. atmospheric
B. absolute
C. vacuum
D. gage
Answer» C. vacuum
9.

In an exothermic chemical reactor, the manipulated variable is the flow rate of

A. coolant
B. reactants
C. product
D. none of these
Answer» B. reactants
10.

Composition of alloys can be determined by

A. polarograph
B. chromatograph
C. refractrometer
D. none of these
Answer» B. chromatograph
11.

Gain margin is equal to the

A. amplitude ratio
B. reciprocal of amplitude ratio
C. gain in P controller
D. gain in P-I controller
Answer» C. gain in P controller
12.

Water is flowing through a series of four tanks and getting heated as shown in figure. It is desired to design a cascade control scheme for controlling the temperature of water leaving the tank 4 as there is a disturbance in the temperature of a second stream entering the tank 2. Select the best place to take the secondary measurement for the second loop.

A. Tank 1
B. Tank 2
C. Tank 3
D. Tank 4
Answer» D. Tank 4
13.

Flow rate through an orifice is __________ the pressure differential.

A. proportional to
B. inversely proportional to the square root of
C. proportional to the square root of
D. inversely proportional to the square of
Answer» D. inversely proportional to the square of
14.

The root locus method, a pole of a transfer function G(s) is the value of s for which G(s) approaches

A. -1
B. 0
C. 1
D. ‚àû
Answer» E.
15.

Thermal wells are used in the temperature measurement to

A. guard against corrosive and oxidising action on thermocouple materials
B. reduce measuring lag.
C. increase the fidelity.
D. increase the sensitivity.
Answer» B. reduce measuring lag.
16.

Mercury thermometer can be used to measure the temperature upto __________ °C.$

A. 100
B. 250
C. 350
D. 750
Answer» D. 750
17.

On-off controllers are normally used for

A. low loads
B. temperature changes
C. flow rate changes
D. none of these
Answer» B. temperature changes
18.

__________ thermometer can not measure sub-zero (< 0° C) temperature,$

A. Mercury in glass
B. Bimetallic
C. Vapor pressure
D. Resistance
Answer» C. Vapor pressure
19.

The deflection of the free end of the bimetallic strips in a bimetallic thermometer with temperature is nearly

A. linear
B. non-linear
C. parabolic
D. hyperbolic
Answer» B. non-linear
20.

With increase in temperature, the electrical conductivity of the platinum used in the resistance thermometer

A. increases
B. decreases
C. remains constant
D. increases exponentially
Answer» C. remains constant
21.

Routh stability method uses __________ loop transfer function.

A. open
B. closed
C. either (a) or (b)
D. neither (a) nor (b)
Answer» C. either (a) or (b)
22.

Which of the following is not classified as a thermo electric pyrometer ?

A. Resistance thermometer.
B. Thermocouple.
C. Optical pyrometer (disappearing filament type)
D. Radiation pyrometer
Answer» D. Radiation pyrometer
23.

Humidity of air can be determined by a

A. chromatograph
B. sling psychrometer
C. mass spectrometer
D. polarimeter
Answer» C. mass spectrometer
24.

The time constant of a first order process with resistance R and capacitance C is

A. R + C
B. R - C
C. RC
D. 1/RC
Answer» D. 1/RC
25.

Temperature measurement range of iron-constantan thermocouple is 0 to 870°C. It can be used to measure sub zero temperature, because at lower temperature$

A. emf produced is very low of the order of microvolt.
B. embrittlement of iron occurs.
C. rusting of iron takes place.
D. both (b) and (c).
Answer» E.
26.

The calibration data of a thermocouple with its cold junction at 0°C are given below.The hot junction of the thermocouple is placed in a bath at 80°C, while its cold junction is at 20°C. What is the emf of thermocouple ?$

A. 3.26 mv
B. 0.80 mv
C. 2.46 mv
D. 2.43 mv
Answer» D. 2.43 mv
27.

Silver point temperature is __________ °C.$

A. 760.5
B. 860.5
C. 960.5
D. 1060.5
Answer» D. 1060.5
28.

Optical activity of a solution can be determined using a

A. polarimeter
B. polarograph
C. dilatometer
D. refractrometer
Answer» B. polarograph
29.

Which of the following is a 'contact' pyrometer ?

A. resistance pyrometer
B. optical pyrometer
C. radiation pyrometer
D. infra red pyrometer
Answer» B. optical pyrometer
30.

In Bode plot, A.R. vs. w is plotted on a/an __________ graph paper.

A. log-lag
B. triangular
C. ordinary
D. semi-log
Answer» B. triangular
31.

For measuring the temperature of a red hot furnace, which is the most suitable instrument ?

A. Platinum resistance thermometer
B. Thermocouple
C. Optical pyrometer
D. Bimetallic thermometer
Answer» D. Bimetallic thermometer
32.

Specific conductance is defined as the reciprocal of resistance in ohms of 1c.c. of liquid at a specified temperature. Its value for distilled water is about __________ micro mho/cm3.

A. 50
B. 100
C. 10
D. 1
Answer» E.
33.

To increase the speed of response of a pressure spring liquid or gas expansion thermometer, the clearance space between the thermometer bulb and the thermal well should not be filled with

A. air
B. a metal powder or graphite
C. oil
D. mercury
Answer» B. a metal powder or graphite
34.

Dead zone in an instrument must be less than __________ percent of the scale.

A. 0.2
B. 1.5
C. 4
D. 8
Answer» B. 1.5
35.

The amplitude ratio for the sinusoidal response of __________ is < 1.

A. transportation lag
B. first order system
C. second order system
D. none of these
Answer» C. second order system
36.

Working principle of mercury in glass thermometer is based on the __________ of mercury with increase in temperature.

A. increase of pressure
B. increase of thermal conductivity
C. volumetric expansion
D. differential linear expansion
Answer» D. differential linear expansion
37.

Concentration of sugar solution can be determined by the

A. polarimetry
B. flame photometry
C. emission spectroscopy
D. oscillometry
Answer» B. flame photometry
38.

What is the normal percentage of rhodium in platinum + rhodium element used in the thermocouple ?

A. 0.1
B. 3
C. 13
D. 29
Answer» D. 29
39.

Stalagmometer is used for the measurement of

A. kinematic viscosity
B. surface tension
C. refractive index
D. optical activity
Answer» C. refractive index
40.

All the thermocouples used for temperature measurement use dissimilar metal

A. strips
B. bars
C. wires
D. beads
Answer» D. beads
41.

Liquid argon level in a pressurised storage tank (at 3 kg/cm2 ) is measured by a/an

A. gage glass
B. external float gage
C. differential pressure gage
D. none of these
Answer» D. none of these
42.

Pick out the most suitable instrument for measuring temperature in the range of-40 to 425°C.$

A. mercury thermometer
B. bimetallic thermometer
C. radiation pyrometer
D. none of these
Answer» C. radiation pyrometer
43.

Range of hydrogen gas constant volume themometer is __________ °C.$

A. -10 to 20
B. 0 to 100
C. 100 - 500
D. 400 - 1000
Answer» C. 100 - 500
44.

Configuration of Bourdon spring tube is never made of __________ shape.

A. circular
B. semi-circular
C. helical
D. spiral
Answer» B. semi-circular
45.

Stability of a control system containing a transportation lag can be best analysed by

A. Routh test
B. root locus methods
C. frequency response methods
D. none of these
Answer» D. none of these
46.

Nickel percentage in invar which is an iron-nickel alloy, and is used as a thermocouple material is

A. 12
B. 36
C. 54
D. 68
Answer» C. 54
47.

For two non-interacting first order systems connected in series, the overall transfer function is the __________ of the individual transfer functions.

A. product
B. ratio
C. sum
D. difference
Answer» B. ratio
48.

Liquid levels in autocalves are measued by

A. simple float
B. differential float type manometer
C. glass gauge
D. none of these
Answer» C. glass gauge
49.

For the block diagram shown below :The characteristic equation is

A. τl S (τps + 1) + Kc . Kp (τlS + 1) e-τd s = 0
B. (τmS + 1) (τpS + 1) + Km . Kp e-τd S = 0
C. τl S(τm S + 1) (τp S + 1) +Kc . Kp . Km (τl s + 1) e-τdS = 0
D. (τms + 1) (τp s + 1) + Kc . Kp . Km . e-τdS = 0
Answer» D. (œÑms + 1) (œÑp s + 1) + Kc . Kp . Km . e-œÑdS = 0
50.

__________ temperature scale assigns 0° to the 'ice point' and 80° to the 'steam point'.$

A. Celcius
B. Rankine
C. Reumur
D. Farenhite
Answer» D. Farenhite