Mechanical Engineering MCQs

Option A: allotropic change

Option B: recrystallisation

Option C: heat treatment

Option D: precipitation

Correct Answer: allotropic change ✔

Option A: high tensile strength

Option B: its elastic limit close to the ultimate breaking strength

Option C: high ductility

Option D: all of the above

Correct Answer: its elastic limit close to the ultimate breaking strength ✔

Option A: free form

Option B: combined form

Option C: nodular form

Option D: flat form

Correct Answer: partly in free and partly in combined state ✔

Option A: compressive strength

Option B: ductility

Option C: carbon content

Option D: hardness

Correct Answer: ductility ✔

Option A: made by adding carbon in steel

Option B: refined from cast iron

Option C: an alloy of iron and carbon with varying quantities of phosphorus and sulphur

Option D: extensively used for making cutting tools

Correct Answer: an alloy of iron and carbon with varying quantities of phosphorus and sulphur ✔

Option A: which are destroyed by burning

Option B: which after their destruction are recycled to produce fresh steel

Option C: which are deoxidised in the ladle with silicon and aluminium

Option D: in which carbon is completely burnt

Correct Answer: which are deoxidised in the ladle with silicon and aluminium ✔

Option A: carbon

Option B: vanadium

Option C: manganese

Option D: cobalt

Correct Answer: vanadium ✔

Option A: 0.025%

Option B: 0.06%

Option C: 0.1%

Option D: 0.25%

Correct Answer: 0.025% ✔

Option A: chromium and nickel

Option B: sulphur, phosphorus, lead

Option C: vanadium, aluminium

Option D: tungsten, molybdenum, vanadium, chromium

Correct Answer: chromium and nickel ✔

Option A: mild steel

Option B: alloy steel

Option C: high carbon

Option D: tungsten steel

Correct Answer: high carbon ✔

Option A: providing corrosion resistance

Option B: improving machining properties

Option C: providing high strength at elevated temperatures

Option D: raising the elastic limit

Correct Answer: improving machining properties ✔

Option A: 0.02%

Option B: 0.3%

Option C: 0.63%

Option D: 0.8%

Correct Answer: 0.8% ✔

Option A: nickel, copper

Option B: nickel, molybdenum

Option C: zinc, tin, lead

Option D: nickel, lead and tin

Correct Answer: nickel, copper ✔

Option A: silver metal

Option B: duralumin

Option C: Hastelloy

Option D: monel metal

Correct Answer: invar ✔

Option A: cast iron

Option B: forged steel

Option C: mild steel

Option D: high carbon steel

Correct Answer: high carbon steel ✔

Option A: ductile

Option B: malleable

Option C: homogeneous

Option D: isotropic

Correct Answer: isotropic ✔

Option A: dipping steel in cyanide bath

Option B: reacting steel surface with cyanide salts

Option C: adding carbon and nitrogen by heat treatment of steel to increase its surface hardness

Option D: obtaining cyanide salts

Correct Answer: adding carbon and nitrogen by heat treatment of steel to increase its surface hardness ✔

Option A: hysteresis

Option B: creep

Option C: visco elasticity

Option D: Boeschinger effect

Correct Answer: Boeschinger effect ✔

Option A: 600 VPN

Option B: 1500 VPN

Option C: 1000 to 1100 VPN

Option D: 250 VPN

Correct Answer: 1000 to 1100 VPN ✔

Option A: cast iron

Option B: mild steel

Option C: non-ferrous materials

Option D: wrought iron

Correct Answer: stainless steel ✔

Option A: RC 65

Option B: RC 48

Option C: RC 57

Option D: RC 80

Correct Answer: RC 48 ✔

Option A: substitutional solid solution

Option B: interstitial solid solution

Option C: intermetallic compounds

Option D: all of the above

Correct Answer: substitutional solid solution ✔

Option A: aluminium

Option B: tin

Option C: zinc

Option D: lead

Correct Answer: silver ✔

Option A: refine grain structure

Option B: reduce segregation in casting

Option C: improve mechanical properties

Option D: induce stresses-

Correct Answer: induce stresses- ✔

Option A: in which atoms align themselves in a geometric pattern upon solidification

Option B: in which there is no definite atomic structure and atoms exist in a random pattern just as in a liquid

Option C: which is not attacked by phosphorous

Option D: which emits fumes on melting

Correct Answer: in which there is no definite atomic structure and atoms exist in a random pattern just as in a liquid ✔

Option A: zinc

Option B: lead

Option C: silver

Option D: glass

Correct Answer: glass ✔

Option A: electroplating

Option B: cyaniding

Option C: induction hardening

Option D: nitriding

Correct Answer: electroplating ✔

Option A: improves wear resistance, cutting ability and toughness

Option B: refines grain size and produces less tendency to carburisation, improves corrosion and heat resistant properties

Option C: improves cutting ability and reduces hardenability

Option D: gives ductility, toughness, tensile strength and anticorrosion properties

Correct Answer: improves wear resistance, cutting ability and toughness ✔

Option A: brass

Option B: cast iron

Option C: aluminium

Option D: steel

Correct Answer: steel ✔

Option A: cobalt

Option B: nickel

Option C: vanadium

Option D: iron

Correct Answer: cobalt ✔

Option A: improve machinability

Option B: improve ductility

Option C: improve toughness

Option D: release stresses

Correct Answer: improve machinability ✔

Option A: promotes decarburisation

Option B: provides high hot hardness

Option C: forms very hard carbides and thus in-creases wear resistance

Option D: promotes retention of austenite

Correct Answer: forms very hard carbides and thus in-creases wear resistance ✔

Option A: RC 65

Option B: RC 48

Option C: RC 57

Option D: RC 80

Correct Answer: RC 57 ✔

Option A: relieve stresses

Option B: harden steel slightly

Option C: improve machining characteristic

Option D: soften material

Correct Answer: harden steel slightly ✔

Option A: substitutional solution

Option B: interstitial solid solution

Option C: intermetallic compounds

Option D: all of the above

Correct Answer: interstitial solid solution ✔

Option A: hot working

Option B: tempering

Option C: normalising

Option D: annealing

Correct Answer: annealing ✔

Option A: RC 65

Option B: RC 48

Option C: RC 57

Option D: RC 80

Correct Answer: RC 65 ✔

Option A: formation of bainite structure

Option B: carburised structure

Option C: martenistic structure

Option D: lamellar layers of carbide distributed throughout the structure

Correct Answer: formation of bainite structure ✔

Option A: hardening surface of workpiece to ob-tain hard and wear resistant surface

Option B: heating and cooling rapidly

Option C: increasing hardness throughout

Option D: inducing hardness by continuous process

Correct Answer: hardening surface of workpiece to ob-tain hard and wear resistant surface ✔

Option A: tin, antimony, copper

Option B: tin and copper

Option C: tin and lead

Option D: lead and zinc

Correct Answer: tin and copper ✔

Option A: nickel, chromium and iron

Option B: nickel, copper

Option C: nickel, chromium

Option D: nickel, zinc

Correct Answer: nickel, chromium and iron ✔

Option A: mild steel

Option B: cast iron

Option C: H.S.S.

Option D: high carbon

Correct Answer: high carbon ✔

Option A: silver and some impurities

Option B: refined silver

Option C: nickel, copper and zinc

Option D: nickel and copper

Correct Answer: nickel, copper and zinc ✔

Option A: aluminium, copper etc

Option B: nickel, molybdenum etc

Option C: nickel, copper, etc

Option D: all of the above

Correct Answer: nickel, molybdenum etc ✔

Option A: sulphur, lead, phosphorous

Option B: silicon, aluminium, titanium

Option C: vanadium, aluminium

Option D: chromium, nickel

Correct Answer: sulphur, lead, phosphorous ✔

Option A: nickel

Option B: chromium

Option C: tungsten

Option D: vanadium

Correct Answer: chromium ✔

Option A: flywheel of steam engine

Option B: cast iron pipes”

Option C: cycle chains

Option D: gas turbine blades

Correct Answer: gas turbine blades ✔

Option A: 0.025%

Option B: 0.26%

Option C: 0.8%

Option D: 1.25%

Correct Answer: 1.7%. ✔

Option A: amount of carbon it contains

Option B: the shape and distribution of the car-bides in iron

Option C: method of fabrication

Option D: contents of alloying elements

Correct Answer: the shape and distribution of the car-bides in iron ✔

Option A: malleable iron

Option B: nodular iron

Option C: spheroidal iron

Option D: grey iron

Correct Answer: malleable iron ✔

Option A: 80% or more iron

Option B: 50% or more iron

Option C: alloying elements like chromium, tungsten nickel and copper

Option D: elements like phosphorus, sulphur and silicon in varying quantities

Correct Answer: 50% or more iron ✔

Option A: tenacity

Option B: brittleness

Option C: plasticity

Option D: corrosion resistance

Correct Answer: hardness ✔

Option A: free carbon

Option B: graphite

Option C: cementite

Option D: white carbon

Correct Answer: cementite ✔

Option A: no graphite

Option B: a very high percentage of graphite

Option C: a low percentage of graphite

Option D: graphite as its basic constituent of composition

Correct Answer: no graphite ✔

Option A: paramagnetic

Option B: ferromagnetic

Option C: ferroelectric

Option D: dielectric

Correct Answer: ferromagnetic ✔

Option A: hard’

Option B: soft

Option C: ductile

Option D: tough

Correct Answer: hard’ ✔

Option A: face-centred cubic lattice

Option B: body-centred cubic lattice

Option C: hexagonal close-packed lattice

Option D: all of the above

Correct Answer: face-centred cubic lattice ✔

Option A: cementite

Option B: free carbon

Option C: flakes

Option D: spheroids

Correct Answer: nodular aggregates of graphite ✔

Option A: cementite

Option B: free carbon

Option C: flakes

Option D: spheroids

Correct Answer: flakes ✔

Option A: malleability

Option B: ductility

Option C: surface finish

Option D: damping characteristics

Correct Answer: damping characteristics ✔

Option A: 0.5 to 1%

Option B: 1 – 2%

Option C: 2.5 to 4.5%

Option D: 5 – 7%

Correct Answer: 2.5 to 4.5% ✔

Option A: the points where no further change oc-curs

Option B: constant for all metals

Option C: the points where there is no further flow of metal

Option D: the points of discontinuity

Correct Answer: the points of discontinuity ✔

Option A: body centred cubic

Option B: face centred cubic

Option C: hexagonal close packed

Option D: cubic structure

Correct Answer: body centred cubic ✔

Option A: molecular change

Option B: physical change

Option C: allotropic change

Option D: solidus change

Correct Answer: allotropic change ✔

Option A: below 723°C

Option B: 770 – 910°C

Option C: 910-1440°C

Option D: 1400-1539°C

Correct Answer: below 723°C ✔

Option A: 770°C

Option B: 910°C

Option C: 1050°C

Option D: below recrystallisation temperature

Correct Answer: 770°C ✔

Option A: austenite

Option B: pearlite

Option C: ferrite

Option D: cementlte

Correct Answer: ferrite ✔

Option A: has a fixed structure under all conditions

Option B: exists in several crystal forms at different temperatures

Option C: responds to heat treatment

Option D: has its atoms distributed in a random pattern

Correct Answer: exists in several crystal forms at different temperatures ✔

Option A: stages at which allotropic forms change

Option B: stages at which further heating does not increase temperature for some time

Option C: stages at which properties do not change with increase in temperature

Option D: there is nothing like points of arrest

Correct Answer: stages at which allotropic forms change ✔

Option A: increase

Option B: decrease

Option C: remain same

Option D: first increase and then decrease

Correct Answer: increase ✔

Option A: creep

Option B: hot tempering

Option C: hot hardness

Option D: fatigue

Correct Answer: hot hardness ✔

Option A: elastic properties in all directions

Option B: stresses induced in all directions

Option C: thermal properties in all directions

Option D: electric and magnetic properties in all directions

Correct Answer: elastic properties in all directions ✔

Option A: in which parts are not loaded

Option B: in which stress remains constant on in-creasing load

Option C: in which deformation tends to loosen the joint and produces a stress reduced

Option D: stress reduces on increasing load

Correct Answer: in which deformation tends to loosen the joint and produces a stress reduced ✔

Option A: low carbon steel

Option B: medium carbon steel

Option C: high carbon steel

Option D: alloy steel

Correct Answer: low carbon steel ✔

Option A: ability to undergo large permanent deformations in compression

Option B: ability to recover its original form

Option C: ability to undergo large permanent deformations in tension

Option D: all of the above

Correct Answer: ability to undergo large permanent deformations in compression ✔

Option A: Unaltered

Option B: Increased

Option C: Decreased

Option D: Advanced

Correct Answer: Advanced ✔

Option A: feed petrol into cylinder

Option B: govern the engine

Option C: break up and mix the petrol with air

Option D: heat up the charge to cylinder

Correct Answer: break up and mix the petrol with air ✔

Option A: 0.334027778

Option B: 0.500694444

Option C: 0.625694444

Option D: 0.834027778

Correct Answer: 0.625694444 ✔

Option A: concentric type

Option B: eccentric type

Option C: horizontal type

Option D: vertical type

Correct Answer: concentric type ✔

Option A: high compression ratio

Option B: low compression ratio

Option C: low volumetric efficiency

Option D: minimum turbulence

Correct Answer: high power output and high thermal efficiency ✔

Option A: Maximum

Option B: Optimum

Option C: Poor

Option D: Constant

Correct Answer: Poor ✔

Option A: clearance volume

Option B: swept volume

Option C: compression ratio

Option D: volumetric efficiency

Correct Answer: compression ratio ✔

Option A: higher knocking will occur

Option B: efficiency will be low

Option C: low power will be produced

Option D: black smoke will be produced

Correct Answer: higher knocking will occur ✔

Option A: the shape and layout of the piston crown, the inlet port, and the valve produce the turbulent effect of fuel mixture

Option B: fuel is injected into an auxiliary chamber that is separated from the cylinder by an orifice or throat

Option C: only a part of air charge is contained in an auxiliary chamber in which the fuel starts to burn with insufficient air which due to explosion tendency mixes thoroughly into main cylinder charge

Option D: there are no valves

Correct Answer: fuel is injected into an auxiliary chamber that is separated from the cylinder by an orifice or throat ✔

Option A: Supercharged

Option B: Not supercharged

Option C: Charged

Option D: Supercharged provided its speed is low

Correct Answer: Not supercharged ✔

Option A: suction port and exhaust port

Option B: transfer port only

Option C: suction port and transfer port

Option D: transfer port and exhaust port

Correct Answer: suction port, exhaust port and transfer port ✔

Option A: size of flywheel

Option B: weight of engine

Option C: type of lubrication system

Option D: absence of valves

Correct Answer: absence of valves ✔

Option A: Zero

Option B: 5-10%

Option C: Depends on load

Option D: Considerable percent

Correct Answer: Zero ✔

Option A: increase

Option B: decrease

Option C: remain unaffected

Option D: increase/decrease depending upon engine capacity

Correct Answer: increase ✔

Option A: The shape and layout of the pistion crown, the inlet port, and the valve produce the turbulent effect of fuel mixture

Option B: Fuel is injected into an auxiliary chamber that is separated from the cylinder by an orifice or throat

Option C: Only a part of air charge is contained in an auxiliary chamber in which the fuel starts to burn with insufficient air which due to explosion tendency mixes thoroughly into main cylinder charge

Option D: There are no valves

Correct Answer: Only a part of air charge is contained in an auxiliary chamber in which the fuel starts to burn with insufficient air which due to explosion tendency mixes thoroughly into main cylinder charge ✔

Option A: 10 kg/cm2

Option B: 100 kg/cm2

Option C: 500 kg/cm2

Option D: 1400 kg/cm2

Correct Answer: 1400 kg/cm2 ✔

Option A: Zero

Option B: 5-10%

Option C: Depends on load and quality of fuel

Option D: Considerable percent

Correct Answer: Considerable percent ✔

Option A: Half

Option B: One

Option C: Two

Option D: Four

Correct Answer: One ✔

Option A: Decreases

Option B: Increases

Option C: Remains same

Option D: Decreases upto a limit and then increases

Correct Answer: Decreases ✔

Option A: 90%

Option B: 50%

Option C: 40%

Option D: 30%

Correct Answer: 30% ✔

Option A: quantity governing

Option B: quality governing

Option C: combined governing

Option D: partial governing

Correct Answer: quantity governing ✔

Option A: quantity governing

Option B: quality governing

Option C: combined governing

Option D: partial governing

Correct Answer: quality governing ✔

Option A: 100%

Option B: 50%

Option C: 5%

Option D: 30%

Correct Answer: 30% ✔

Option A: 2%

Option B: 4%

Option C: 8%

Option D: ±4%

Correct Answer: 4% ✔

Option A: give lot of smoke

Option B: detonate

Option C: knock

Option D: not run

Correct Answer: not run ✔