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.

________________ is the hardest material out of the following ?

A. Boron carbide
B. Tungsten carbide
C. Hardened steel
D. Silicon carbide
Answer» B. Tungsten carbide
2.

______________ is not used as the control rod material in a nuclear reactor ?

A. Cobalt
B. Hafnium
C. Cadmium
D. Boron
Answer» B. Hafnium
3.

_________________ is not used as a material of construction in thermocouples ?

A. Alumel
B. Rhodium
C. Constantan
D. Duralumin
Answer» E.
4.

_________________ is not a heat treatment process ?

A. Cyaniding
B. Parkerizing
C. Austempering
D. Martempering
Answer» C. Austempering
5.

_______________ is not a case hardening process ?

A. Carburising
B. Nitriding
C. Cyaniding
D. Annealing
Answer» B. Nitriding
6.

________________ is a special constituent of chlorophyll without which photosynthesis is not possible ?

A. Calcium
B. Nitrogen
C. Phosphorous
D. Hydrogen
Answer» C. Phosphorous
7.

_______________ is a non volatile film forming constituent of a paint ?

A. Thinner
B. Dryer
C. Drying oil
D. None of these
Answer» D. None of these
8.

______________________ iron is produced by the annealing of white cast iron?

A. Malleable
B. Nodular
C. Ductile
D. Grey
Answer» B. Nodular
9.

Iron content in Indian iron ore is about _________________ percent?

A. 80-85
B. 60-65
C. 40-45
D. 20-25
Answer» C. 40-45
10.

Internal energy of a gas obeying Van-Der-Waals equation of state, [p + (a/v2)] (V – b) = RT, depends upon its___________________?

A. Pressure & temperature
B. Pressure & specific volume
C. Temperature & specific volume
D. Temperature only
Answer» B. Pressure & specific volume
11.

Insulation of liquid surface can be achieved by _____________ on top of its surface?

A. Floating hollow polypropylene spheres
B. Spraying alumina powder
C. Putting cement
D. None of these
Answer» B. Spraying alumina powder
12.

Inertial forces are obtained, when the elastic forces are multiplied by ______________ number?

A. Mach
B. Froude
C. Reynolds
D. Euler
Answer» B. Froude
13.

Induced draft fans provided in large thermal power plant boilers have __________________ blades?

A. Forward curved
B. Backward curved
C. Double curved
D. Radial or straight
Answer» C. Double curved
14.

Increasing the carbon content of steel_________________?

A. Reduces the upper shelf energy
B. Increasing the ductility transition temperature
C. Decreases brittleness
D. Decreases hardness
Answer» C. Decreases brittleness
15.

Increasing sulphur content in pig iron tends to make it ________________?

A. Soft
B. Hard
C. Tough
D. Ductile & malleable
Answer» C. Tough
16.

Increase in temperature, in general results in the____________________?

A. Decrease in the viscosities of both liquids & gases
B. Increase in the viscosities of both liquids & gases
C. Increase in the viscosity of liquids and decrease in that of gases
D. Decrease in the viscosity of liquids and increase in that of gases
Answer» E.
17.

Increase in the entropy of a system represents the_____________________?

A. Degradation of energy
B. Decrease in system pressure
C. Increase in the availability of energy
D. Increase in the temperature
Answer» B. Decrease in system pressure
18.

In troposphere (the weather domain), the temperature ‘t’ at height ‘h’ above the sea level in metres is given by (where, temperature at sea level is 15°C and t is in °C.) ?

A. t = 15 – 0.0065 h
B. t = 15 + 0.0065 h
C. t = 0.0035 h – 15
D. t = 15 – 0.0035 h
Answer» B. t = 15 + 0.0065 h
19.

In TIG welding, thoriated tungsten electrodes are used, because it ____________________?

A. Has higher current carrying capacity
B. Has better electron emissivity
C. Is stronger than ordinary tungsten
D. Is easy to prepare
Answer» C. Is stronger than ordinary tungsten
20.

In the X-ray radiography technique, the tube voltage for thicker plates as compared to thin plates, should be________________?

A. Higher, as it gives higher wavelength
B. Lower, as it gives higher wavelength
C. Higher, as it gives shorter wavelength
D. Lower, as it gives shorter wavelength
Answer» D. Lower, as it gives shorter wavelength
21.

In the diving apparatus, helium is used along with oxygen, because it is ____________________?

A. Easily available
B. Not soluble in blood at high pressure
C. Lighter than nitrogen
D. Completely miscible with oxygen
Answer» C. Lighter than nitrogen
22.

In the blast furnace, incorporation of water vapour in the blast gives the following effect ?

A. Increases the reducing potential of the gas
B. Increases the flame temperature
C. No significant change occurs
D. Increases the hydrogen content in the metal
Answer» B. Increases the flame temperature
23.

In the Bayer’s process, bauxite is digested under pressure using ___________________?

A. H2SO4
B. NaOH
C. NH3
D. HCl
Answer» C. NH3
24.

In the acid Bessemer process, the hot metal should have the following composition ?

A. S < 0.05% and P < 0.05%
B. S < 0.05% and P < 1.5%
C. S 1.5%
D. S > 1.5% and P < 0.05%
Answer» B. S < 0.05% and P < 1.5%
25.

In ________________ process, there is an increase in entropy with no degradation of energy ?

A. Isothermal expansion
B. Isochoric heat addition
C. Polytropic expansion
D. Isobaric heat addition
Answer» B. Isochoric heat addition
26.

In practice, the compression ratio of compression-ignition (CI) engine ranges from ______________________?

A. 15 to 25
B. 5 to 10
C. 40 to 55
D. 60 to 70
Answer» B. 5 to 10
27.

In Newton’s law of viscosity, which states that the shear stress is proportional to the _____________ Co-efficient of viscosity is called dynamic or absolute viscosity(where, V = velocity, Vg = velocity gradient) ?

A. V2
B. 1/V2
C. 1/Vg
D. Vg
Answer» E.
28.

In multipass welds, shot peening is done after each pass to__________________?

A. Close the surface porosity
B. Break the continuity of columnar grains
C. Flatten the weldment
D. Introduce texture in the weld
Answer» B. Break the continuity of columnar grains
29.

In inventory control theory, the economic order quantity (EOQ) is the____________________?

A. Lot size corresponding to break even analysis
B. Average level of inventory
C. Optimum lot size
D. None of these
Answer» D. None of these
30.

In “Imperial Smelting Process” for extraction of zinc, zinc vapour thus produced is quenched in the external condenser by the use of the following _______________________?

A. Jet of water at high pressure
B. Blast of air
C. Mixture of water and air
D. Rain of molten lead
Answer» E.
31.

In electrical resistance welding, distortion results from the use of improper________________?

A. Clamping methods
B. Electrodes
C. Current
D. Filler material
Answer» B. Electrodes
32.

In connection with corrosion of metals, passivation is the process that__________________?

A. Intensifies deterioration
B. Changes the composition of the metal
C. Inhibits further deterioration
D. None of these
Answer» D. None of these
33.

In condensers used in thermal power plants, steam is normally used in shell side and cooling water on the tube side, because of the reason that ?

A. Compared to the mass flow rate of cooling water, the rate of condensation of steam is invariably smaller
B. Maintaining vacuum on tube side is more difficult than that on the shell side
C. Water velocity can be increased conveniently to increase the overall heat transfer co-efficient because of its lower specific volume compared to steam
D. Condenser can act as a storage unit for condensed steam
Answer» D. Condenser can act as a storage unit for condensed steam
34.

In chemical dehumidification of air___________________?

A. Both specific humidity & dry bulb temperature increases
B. Both specific humidity & dry bulb temperature decreases
C. Specific humidity decreases & dry bulb temperature increases
D. Specific humidity increases & dry bulb temperature decreases
Answer» D. Specific humidity increases & dry bulb temperature decreases
35.

In case of water (Prandtl number ≈ 6) flowing over a flat plate heated over the entire length, the thermal boundary layer thickness as compared to hydrodynamic boundary layer thickness is ?

A. Less
B. More
C. Equal
D. Unpredictable
Answer» B. More
36.

In case of simple harmonic motion, displacement is proportional to the_________________?

A. Velocity
B. Acceleration
C. Both A. & B.
D. Neither A. nor B.
Answer» C. Both A. & B.
37.

In case of condensers & evaporators operating under given terminal conditions, LMTD (logarithmic mean temperature difference) for counter flow as compared to that for parallel flow is__________________?

A. More
B. Less
C. Equal
D. Much more
Answer» D. Much more
38.

In case of compression of one kg of air, the work done will be the least, when the value of polytropic index ‘n’ is______________________?

A. 1
B. 1.4
C. 1.5
D. Y = Cp/Cv
Answer» B. 1.4
39.

In case of brasses, with decreasing zinc percentage and increasing copper percentage, its _____________ increases ?

A. Percentage elongation
B. Brinell hardness
C. Tensile strength
D. All A, B & C
Answer» B. Brinell hardness
40.

In case of a, centrifugal pump, the ratio h1/h2 is termed as the _____________ efficiency (where, h1 = actual measured head & h2 = head imparted to the fluid by impeller)?

A. Mechanical
B. Overall
C. Volumetric
D. Impeller
Answer» B. Overall
41.

In a totally irreversible isothermal expansion process for an ideal gas, ΔE = 0, ΔH = 0. Then ΔQ and ΔS will be_______________?

A. ΔQ = 0, ΔS=0
B. ΔQ = 0, ΔS = +ve
C. ΔQ = 0, ΔS = -ve
D. ΔQ = +ve, ΔS= +ve
Answer» C. ΔQ = 0, ΔS = -ve
42.

In a neutral solution__________________?

A. H+ ions are absent
B. OH- ions are absent
C. Both H+ and OH- ions are present in very small but equal concentration
D. None of these
Answer» D. None of these
43.

In a good rimming steel_________________________?

A. Carbon and silicon should be low
B. Silicon should be low but carbon should be high
C. Both silicon & carbon should be high
D. Silicon should be high but carbon should be low
Answer» B. Silicon should be low but carbon should be high
44.

In a furnace with heating element temperature at 1700°C, the dominant mechanism of heat transfer will be__________________?

A. Conduction
B. Radiation
C. Natural convection
D. Forced convection
Answer» C. Natural convection
45.

In a forced draft cooling tower, water is cooled from 95 to 80°F by exposure to air with a wet bulb temperature of 70°F. In this case, the________________?

A. Range is 15°F
B. Approach is 10°F
C. Both A. & B.
D. Neither A. nor B.
Answer» D. Neither A. nor B.
46.

In a drilling process, the metal is removed by both shearing & extrusion. General purpose drills are made of_________________?

A. Stainless steel
B. Mild steel
C. High speed steel
D. High carbon steel
Answer» D. High carbon steel
47.

In a counter flow heat exchanger, hot fluid enters at 170°C & leaves at 150°C, while the cold fluid enters at 50°C & leaves at 70°C. The arithmetic mean temperature difference in this case is ______________ °C?

A. 20
B. 60
C. 120
D.
Answer» E.
48.

In a boundary layer developed along the flow, the pressure decreases in the downstream direction. The boundary layer thickness in this case will _______________?

A. Decrease gradually
B. Increase gradually
C. Increase rapidly
D. Remain constant
Answer» C. Increase rapidly
49.

If the head is doubled in & centrifugal pump, the power required will increase in the ratio of__________________?

A. 23
B. 23/2
C. 25/2
D. 21/3
Answer» C. 25/2
50.

If the demand for an item is trebled and the order cost is reduced to one third, then the economic order quantity_________________?

A. Is trebled
B. Remains unchanged
C. Decreases by a factor of 3
D. Decreases by a factor of 1/3
Answer» C. Decreases by a factor of 3