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.

A common disinfectant used in village wells for disinfection of water is

A. free chlorine
B. bromine
C. iodine
D. potassium permanganate
Answer» E.
2.

Superheating of steam is done at constant

A. enthalpy
B. entropy
C. pressure
D. volume
Answer» D. volume
3.

The expected efficiency of a single rivetted lap joint is of the order of 50%. If the thickness of the plate is increased four times, then the rivet diameter will have to be increased __________ times.

A. two
B. four
C. six
D. eight
Answer» B. four
4.

Nickel and __________ are the alloying element added in steel to increase its toughness.

A. molybdenum
B. chromium
C. vanadium
D. silicon
Answer» E.
5.

Which of the following equipments is used for liquid dispersion ?

A. Packed column
B. Venturi scrubber
C. Bubble cap plate column
D. Wetted wall column
Answer» C. Bubble cap plate column
6.

The dimensional formula of bulk modulus of elasticity is same as that of the

A. pressure
B. density
C. force
D. none of these
Answer» B. density
7.

Ferromagnetic material owe their properties to __________ inner sub-shells.

A. completely filled
B. partially filled
C. equally filled
D. vacant
Answer» C. equally filled
8.

Which of the following metals is the most prone to work hardening?

A. Brass
B. Aluminium
C. Copper
D. Lead
Answer» B. Aluminium
9.

Eutectoid composition of carbon steel at room temperature is

A. cementite
B. pearlite
C. martensite
D. ferrite
Answer» C. martensite
10.

The friction factor for the turbulent fluid flow in a rough pipe does not depend upon the

A. pipe roughness & pipe diameter.
B. fluid velocity.
C. type of flowing fluid.
D. both 'b' & 'c'.
Answer» E.
11.

Flue gases pass through the following boiler accessories in a high pressure natural circulation boiler.A. Induced draft fan B. Economiser C. Air preheater D. Steam superheater Which of the following gives the correct sequence of flow of the flue gases through the above mentioned boiler accessories ?

A. A, C, B, D
B. D, B, C, A
C. D, C, B, A
D. D, A, B, C
Answer» C. D, C, B, A
12.

Mild steel has __________ crystal lattice structure.

A. face centred cubic (fcc)
B. body centred cubic (bcc)
C. orthorhombic
D. cubic
Answer» C. orthorhombic
13.

Which of the following does not have a sharp melting point ?

A. Thoria
B. Glass
C. Ice
D. Pig iron
Answer» C. Ice
14.

Aluminium is extracted from

A. chalcocite
B. bauxite
C. galena
D. none of these
Answer» C. galena
15.

__________ fluid force is not considered in the Navier-Stokes equation.

A. Turbulent
B. Viscous
C. Gravity
D. Pressure
Answer» B. Viscous
16.

What is the value of entropy at 273 K ?

A. 0
B. 1
C.
D. none of these
Answer» B. 1
17.

Case hardening of a material is

A. followed by tempering or carburising.
B. preceded by its tempering.
C. done to get a soft ductile interior with a very hard surface.
D. carried out to get extreme hardness in its core.
Answer» E.
18.

In the formation of cermets, the ratio of ceramic material to metallic material is usually 80:20. Which of the following is a cermet ?

A. Zirconia
B. Alumina
C. Bakelite
D. Tungsten carbide
Answer» E.
19.

The phenomenon occurring during explosion of a hydrogen bomb is

A. nuclear fission.
B. nuclear fusion.
C. a combination of both nuclear fission & fusion.
D. none of these.
Answer» D. none of these.
20.

Square steel key is normally strong in failure by shear & crushing. Keys are normally made of __________ steel bars.

A. hot rolled mild
B. cold rolled mild
C. forged
D. machinable stainless
Answer» C. forged
21.

Nitriding of a steel part does not increase its

A. grain size.
B. fatigue limit.
C. surface hardness.
D. wear resistance.
Answer» B. fatigue limit.
22.

__________ of grey cast iron produces white cast iron.

A. Tempering
B. Rapid heating
C. Rapid cooling
D. Slow cooling
Answer» C. Rapid cooling
23.

As the fluid flow rate increases, the float of the rotameter

A. rises in the tube.
B. rotates at higher speed.
C. rotates at lower speed.
D. drops down in the tube.
Answer» B. rotates at higher speed.
24.

Enzymes belong to the category of

A. proteins
B. carbohydrates
C. vitamins
D. fats
Answer» B. carbohydrates
25.

What is the value of included angle of a triangular notch for maximum discharge ?

A. 30
B. 60
C. 90
D. 120
Answer» D. 120
26.

For separating small pieces of metal from engine oil of a car, the best separating technique is the

A. chromatography
B. evaporation
C. filtration
D. fractional distillation
Answer» D. fractional distillation
27.

Heat flow across a hollow sphere of inner radius 'r1' and outer radius 'r2' is directly proportional to

A. <img src="/_files/images/chemical-engineering/chemical-engineering-basics/716-132-1.png">
B. <img src="/_files/images/chemical-engineering/chemical-engineering-basics/716-132-2.png">
C. <img src="/_files/images/chemical-engineering/chemical-engineering-basics/716-132-3.png">
D. <img src="/_files/images/chemical-engineering/chemical-engineering-basics/716-132-4.png">
Answer» C. <img src="/_files/images/chemical-engineering/chemical-engineering-basics/716-132-3.png">
28.

Addition of __________ to steel does not impart hardness.

A. nickel
B. copper
C. chromium
D. silicon
Answer» C. chromium
29.

For a spontaneous natural process at constant temperature and pressure, the free energy of the system always

A. increases.
B. decreases.
C. remains constant.
D. increases to a maximum before decreasing.
Answer» B. decreases.
30.

Inertial forces are obtained, when the elastic forces are multiplied by __________ number.

A. Mach
B. Froude
C. Reynolds
D. Euler
Answer» B. Froude
31.

Temperature of hot gases flowing in a pipe is measured by a thermocouple inserted in the thermal well. The thermal well made of __________ will facilitate the most accurate measurement of the temperature.

A. copper
B. steel
C. aluminium
D. brass
Answer» B. steel
32.

Wavelength of radiation emitted by a body depends on the __________ of its surface.

A. temperature
B. area
C. nature
D. all 'a', 'b' & 'c'
Answer» B. area
33.

Titanium is added to molten aluminium alloys before casting for the purpose of

A. grain refinement.
B. increasing corrosion resistance.
C. reducing porosity.
D. improving fluidity.
Answer» E.
34.

Cemented carbide tools are not suitable for cutting

A. aluminium
B. brass
C. cast iron
D. steel
Answer» B. brass
35.

The difference between gross &amp; net calorific values of fuel is due to the

A. sensible heat carried away by the flue gases.
B. heat carried away by the steam from the moisture content of the fuel.
C. heat lost by radiation.
D. heat carried away by steam from the combustion of hydrogen in the fuel.
Answer» E.
36.

Which of the following is preferred for rivetting ?

A. Lap joint
B. Butt joint
C. Either (a) or (b)
D. Neither (a) nor (b)
Answer» C. Either (a) or (b)
37.

Heating the hypoeutectoid steels to 30 C above the upper critical temperature line, soaking at that temperature and then cooling slowly to the room temperature to form a pearlite &amp; ferrite structure is called

A. tempering
B. hardening
C. annealing
D. normalising
Answer» D. normalising
38.

Commercial production of hydrogen for the manufacture of nitrogeneous fertilisers is done by

A. steam reforming of naphtha and cracking of natural gas.
B. electrolysis of water.
C. cryogenic separation of hydrogen from coke oven gas.
D. all (a), (b) and (c)
Answer» E.
39.

Which fertiliser is made (using coke oven gas) in by products plant of an integrated steel plant ?

A. Urea
B. CAN
C. Ammonium sulphate
D. Superphosphate
Answer» D. Superphosphate
40.

Preheating prior to welding is done for the purpose of

A. decreasing cooling rate.
B. facilitating fusion of high melting metals.
C. preventing hot cracking.
D. ensuring full penetration.
Answer» B. facilitating fusion of high melting metals.
41.

Presence of sulphur in steel reduces the

A. hardness.
B. grain size.
C. tensile strength.
D. toughness & transverse ductility.
Answer» E.
42.

Frother is added in the froth floatation cell used in ore beneficiation to stabilise the air bubbles (i.e., froth), which will hold the ore particles, but it does not affect the floatability of minerals. Which of the following is not used as a frother?

A. Cresylic acid
B. Xanthaies
C. Pine oil
D. all 'a' 'b' & 'c'
Answer» C. Pine oil
43.

Otto cycle used in spark ignition petrol engines is also known as the constant __________ cycle.

A. volume
B. pressure
C. heat
D. none of these
Answer» B. pressure
44.

Fire on fuel oil lines can be extinguished by

A. foam
B. steam
C. water
D. carbon dioxide
Answer» B. steam
45.

Air-petrol ratio in an automotive petrol engine is around

A. 14 : 1
B. 22 : 1
C. 25 : 1
D. 4 : 1
Answer» B. 22 : 1
46.

The property of material, by which a given amount of energy is absorbed by it, without plastic deformation is called

A. resilience
B. toughness
C. ductility
D. impact strength
Answer» B. toughness
47.

Sacrificial anode method is used in the protection of pipelines which are buried underground. Sacrificial anode

A. occurs higher in the electro-chemical series of metals.
B. is exemplified by magnesium plate.
C. is much cheaper than the cathodic base material to be guarded against corrosion.
D. all (a), (b) & (c).
Answer» E.
48.

Electrochemical corrosion can occur, only if __________ is present in contact with metal.

A. air
B. oxygen
C. liquid medium
D. gaseous medium
Answer» D. gaseous medium
49.

Crystallisation of polymers is an undesirable property. Crystallisation of celluloid is prevented by adding

A. glycerol
B. nitro cellulose
C. camphor
D. none of these
Answer» E.
50.

Dryness fraction of dry steam is

A. 0
B.
C. 1
D. 0.5
Answer» D. 0.5