Ssc je mechanical engineering

#sscjemechanical #sscje2018

**SSC Junior Engineer Exam Paper – 2018 “held on 22 January 2018” Morning Shift (Mechanical Engineering) **

**Q 1:** The number of links (I) which is required to form a kinematic chain can be expressed in term of the number of pairs (p) as_______

**Options:**

**1)** I = 2p – 4

**2)** I = 2p – 3

**3)** I = 2p – 2

**4)** I = 2p – 5

**Answer:** I = 2p – 4

**Q 2:** What is the total number of Links and joints in the mechanism as

**Options:**

**1)** 3 and 3

**2)** 3and 2

**3)** 4 and 3

**4)** 4 and 4

**Answer:** 4 and 3

**Q 3:** What is the degree of freedom of the mechanism shown below ?

**Options:**

**1)** 1

**2)** 2

**3)** 3

**4)** 4

**Answer:** 2

**Q 4:** The graph of turning moment diagram is drawn between_______

**Options:**

**1)** Crank angle and crank radius

**2)** Crank angle and crank effort

**3)** Crank effort and crank angle

**4)** Crank radius and crank angle

**Answer:** Crank effort and crank angle

**Q 5:** The mass of flywheel of a steam engine is 3250 kg with the radius of gyration of 1 m. The starting torque of the engine is 4500 N-m. What is the angular acceleration (rad/s^{2}) of the flywheel ?

**Options:**

**1)** 3.4

**2)** 2

**3)** 2.48

**4)** 1.38

**Answer:** 1.38

**Q 6:** A pulley is driven by a flat belt and the maximum tension produced in the belt is of 1400 N. The belt has the density of 1000 kg/m^{3}, 100 mm wide and 5 mm thick. What is the speed (m/sec) of the belt for the maximum power.

**Options:**

**1)** 32

**2)** 31

**3)** 30.55

**4)** 3.05

**Answer:** 30.55

**Q 7:** The rotary internal combustion engine is the inversion of_______

**Options:**

**1)** Four bar link chain

**2)** Double slider crank chain

**3)** Single slider crank mechanism

**4)** Rocker crank mechanism

**Answer:** Single slider crank mechanism

**Q 8:** The pressure distribution in the uniform wear theory is______

**Options:**

**1)** Directly Proportional to radius

**2)** Directly proportional to the square of radius

**3)** Inversely proportional to radius

**4)** Inversely proportional to the square of radius

**Answer:** Inversely proportional to radius

**Q 9:** When the friction lining is new, the wear varies________

**Options:**

**1)** Directly to radius

**2)** Inversely to radius

**3)** Directly to the square of radius

**4)** Inversely to the square of radius

**Answer:** Directly to radius

**Q 10:** What is the radial distance of a tooth from the pitch to the top of the tooth known as ?

**Options:**

**1)** Dedendum

**2)** Addendum

**3)** Pitch circle diameter

**4)** Module

**Answer:** Addendum

**Q 11:** Which of the following statement is **TRUE** about the contact ratio ?

**Options:**

**1)** Varies directly to the length of the arc of contact

**2)** Inversely proportional to the module

**3)** Inversely proportional to the module

**4)** All options are correct

**Answer:** All options are correct

**Q 12:** Which of the following governors does not have central load attached to their sleeves ?

**Options:**

**1)** Hartnell governor

**2)** Proell governor

**3)** Porter governor

**4)** Watt governor

**Answer:** Watt governor

**Q 13:** Which of the following governors does not have central load attached to their sleeves ?

**Options:**

**1)** Porter governor

**2)** Watt governor

**3)** Proell governor

**4)** None of these

**Answer:** Watt governor

**Q 14:** What will be the vertical height (m) of a watt governor, if the speed of rotation is 80 rpm ?

**Options:**

**1)** 1.4

**2)** 1.14

**3)** 0.14

**4)** 0.11

**Answer:** 0.14

**Q 15:** Which of the following term defines the size of the cam ?

**Options:**

**1)** Base circle

**2)** Prime circle

**3)** Pitch circle

**4)** Pitch curve

**Answer:** Base circle

**Q 16:** What term is used for the combined effect of all the forces on a body ?

**Options:**

**1)** Load

**2)** Stress

**3)** Strain

**4)** None of these

**Answer:** Load

**Q 17:** Which of the following load does not act on the considerable length of the beam ?

**Options:**

**1)** Uniformly distributed

**2)** Triangular

**3)** Point

**4)** Uniformly varying

**Answer:** Point

**Q 18:** Which term states the S.I unit of stress ?

**Options:**

**1)** KN/mm

**2)** N/mm^{2}

**3)** N/mm^{3}

**4)** m^{3}/sec

**Answer:** N/mm^{2}

**Q 19:** Maximum shear stress theory was postulated by_______

**Options:**

**1)** ST Venant

**2)** Mohr

**3)** Rankine

**4)** Tresca

**Answer:** Tresca

**Q 20:** The equivalent length of the column when both the ends are fixed is______

**Options:**

**1)** 1

**2)** 1/2

**3)** 1/4

**4)** 2I

**Answer:** 1/2

** **

**Q 21:** The slenderness ratio of the columns is_____

**Options:**

**1)** Directly proportional to the effective length

**2)** Directly proportional to the least radius of gyration

**3)** Directly proportional to the square of effective length

**4)** Directly proportional o the square of least radius of gyration

**Answer:** Directly proportional to the effective length

**Q 22:** Rankine theory is applicable to the______

**Options:**

**1)** Short strut/column

**2)** Long column

**3)** Both short and long column

**4)** None of these

**Answer:** Both short and long column

**Q 23:** Which of the following assumptions is **INCORRECT** about the long column ?

**Options:**

**1)** The column behaves elastically

**2)** The load acts perfectly axial and passes through the centroid of the column section.

**3)** The weight of the column is neglected.

**4)** The material is non-homogeneous and anisotropic.

**Answer:** The material is non-homogeneous and anisotropic.

**Q 24:** What is the maximum shear stress on the wall of a thin cylinder, if it has a diameter of d, thickness of t and the gauge pressure in the cylinder is p ?

**Options:**

**1)** pd / t

**2)** pd / 4t

**3)** pd / 2t

**4)** pd / 8t

**Answer:** pd / 8t

**Q 25:** What is the volumetric strain in the thin cylinder subjected to internal pressure having hoop stress of 200 MPa, modulus of elasticity, E=200 Gpa and poisons ratio=0.25 ?

**Options:**

**1)** 20 / 1000

**2)** 2 / 1000

**3)** 0.2 / 1000

**4)** 0.02 / 1000

**Answer:** 2 / 1000

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**Q 26:** The property of the material to regain its original shape after deformation when the external forces are removed is________

**Options:**

**1)** Plasticity

**2)** Elasticity

**3)** Durability

**4)** None of these

**Answer:** Elasticity

**Q 27:** The correct shear force diagram for the cantilever beam with uniformly distributed load over the whole length of the beam is

** **

**Q 28:** Which of the following is the **CORRECT** bending moment diagram for the cantilever beam carrying uniformly varying load from zero at free and w/unit length at the fixed end ?

**Q 29:** A rod of diamension 20 mm x 20 mm is carrying an axial tensile load of 10 KN. The tensile stress developed is________

**Options:**

**1)** 0.025 Mpa

**2)** 0.25 Mpa

**3)** 25 Mpa

**4)** 250 Mpa

**Answer:** 25 Mpa

**Q 30:** Which is the **CORRECT ** option for the polar moment of Inertia of the solid shaft ?

**Options:**

**1)** J – (π/64) d^{4}

**2)** J – (π/32)d^{4}

**3)** J – (π/16) d^{2}

**4)** J – (π/16)d^{4}

**Answer:** J – (π/32)d^{4 }

**Q 31:** The triple point on a P-V diagram is_______.

**Options:**

**1)** A line

**2)** A point

**3)** A triangle

**4)** Not present

**Answer:** A line

**Q 32:** Which of the following statement related to entropy is TRUE ?

**Options:**

**1)** Minimum entropy is observed when the system is in equilibrium with the surrounding.

**2)** At absolute zero temperature, the solid solutions have non-zero entropy.

**3)** Substance in solid phase has the least entropy.

**4)** Entropy conservation takes place in all irreversible processes.

**Answer:** Substance in solid phase has the least entropy.

**Q 33:** If the COP of Carnot refrigerator is 4, then the thermal efficiency of the Carrot engine would be ______

**Options:**

**1)** 0.33

**2)** 0.25

**3)** 0.2

**4)** 0.18

**Answer:** 0.2

**Q 34:** While working between temperatures 150 K and 300 K, the entropy change experienced by the Carnot engine during heat addition is 1 KJ/K the work produced (KJ) by the engine is______

**Options:**

**1)** 100

**2)** 150

**3)** 300

**4)** 600

**Answer:** 150

**Q 35:** A heat engine working between the source at 200^{o}C and rejects heat at 25^{o}C receives 5 KW of heat. Work done for this engine is equal to 0 KW. Does this satisfy the inequality of Clausius ?

**Options:**

**1)** Yes

**2)** No

**3)** Cannot be determined

**4)** None of these

**Answer:** Yes

**Q 36:** An ideal gas with heat capacity ratio of 2 is used in an ideal Otto-cycle which operates between minimum and maximum temperatures of 200 K and 1800 K. What is the compression ration of the cycle for maximum work output ?

**Options:**

**1)** 1.5

**2)** 2

**3)** 3

**4)** 4

**Answer:** 3

**Q 37:** In an Otto cycle, air is compressed from 3 litres to 2.4 litres from a starting pressure of 1.5 kg/cm^{2}. The net output per cycle is 400 KJ. What is the mean effective pressure (kPa) of the cycle ?

**Options:**

**1)** 500

**2)** 567

**3)** 667

**4)** 700

**Answer:** 667

**Q 38:** The combination in a compression ignition engine is_______

**Options:**

**1)** Heterogeneous

**2)** Homogeneous

**3)** Laminar

**4)** Turbulent

**Answer:** Heterogeneous

**Q 39:** Which relation is the basis of Mollier Diagram ?

**Options:**

**1)** C_{P} = (∂h / ∂T)_{P}

**2)** C_{V} = (∂Q / ∂T)_{T}

**3)** C_{P} – C_{v} = R

**4)** T = (∂h / ∂S)_{P}

**Answer:** T = (∂h / ∂S)_{P}

**Q 40**: Which of the following formula holds **TRUE** for dryness fraction ?

**Options:**

**1)** m_{V} / (m_{v} + m_{I})

**2)** m_{I} / (m_{V} + m_{I})

**3)** (m_{V} + m_{I}) / m_{V}

**4)** (m_{V} + m_{I}) / m_{I}

**Answer:** m_{V} / (m_{v} + m_{I})

**Q 41:** Which gas will produce the highest efficiency in an ideal Otto cycle for same compression ratio ?

**Options:**

**1)** Air

**2)** Carbon dioxide

**3)** Helium

**4)** Oxygen

**Answer:** Helium

**Q 42:** In Mollier diagram, the isotherm in the superheated region at low pressures becomes ______.

**Options:**

**1)** Diverge from one another

**2)** Horizontal

**3)** Parallel

**4)** Vertical

**Answer:** Horizontal

**Q 43:** If the heat rejected from the system is zero, then which of the following will hold **TRUE** ?

**Options:**

**1)** When net work is equal to the heat absorbed, work efficiency is 100%.

**2)** Heat is exchanged from one heat reservoir only.

**3)** It violates Kelvin-Plank statement.

**4)** All options are correct.

**Answer:** All options are correct.

**Q 44:** Clausius’ statement and Kelvin-Plank’s statement are_______.

**Options:**

**1)** Not connected

**2)** Two parallel statements of the second law

**3)** Violation of one does not violates the other

**4)** False statements

**Answer:** Two parallel statements of the second law

**Q 45: **For the same heat added and the same compression ratio,_______

**Options:**

**1)** Otto cycle is more efficient than diesel cycle.

**2)** Diesel cycle is more efficient than Otto cycle.

**3)** Both Diesel and Otto cycle are equally efficient.

**4)** Cannot be determined

**Answer:** Otto cycle is more efficient than diesel cycle.

**Q 46:** A reversible engine operates between temperature T_{1} and T_{2}. The energy rejected by this engine acts as an input for another reversible engine at temperature T_{2}, which rejects to a reservoir at temperature T_{3}. What is the relation between T_{1}, T_{2} and T_{3} ?

**Options:**

**1)** T_{2} = (T_{1} = T_{3}) / 2

**2)** T_{2} = √(T_{1}^{2} + T_{3}^{2})

**3)** T_{2} = √T_{1}T_{3}

**4)** T_{2} = (T_{1} – T_{3}) / 2

**Answer:** T_{2} = √T_{1}T_{3 }

**Q 47:** Which equation defines the enthalpy (h) of a system ?

**Options:**

**1)** U + (pv / J)

**2)** U – (pv / J)

**3)** U + (R / Jpv)

**4)** U + Jpv

**Answer:** U + (pv / J)

**Q 48:** Which gas can attain the highest efficiency for the same compression rise ?

**Options:**

**1)** Any of the gases

**2)** Diatomic gases

**3)** Mono atomic gases

**4)** Tri-atomic gases

**Answer:** Mono atomic gases

**Q 49:** In Clausius theorem the reversible path is substituted by _________.

**Options:**

**1)** Reversible isobars

**2)** Reversible isotherms

**3)** Reversible isochoric

**4)** None of these

**Answer:** Reversible isotherms

**Q 50:** Which of the relation represents an irreversible and possible process ?

**Options:**

**1) **

**2) **

**3) **

**4)** None of these

**Answer: **

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**Q 51:** ________does not certain tin as an alloying element.

**Options:**

**1)** Babbitt metal

**2)** White metal

**3)** Solder

**4)** All options are correct

**Answer:** White metal

**Q 52:** Under microscope ferrite appears as

**Options:**

**1)** White

**2)** Light

**3)** Dark

**4)** None of these

**Answer:** White

**Q 53:** _______structure is obtained by austempering process of heat treatment.

**Options:**

**1)** Sorbite

**2)** Bainite

**3)** Martensite

**4)** Troostite

**Answer:** Bainite

**Q 54:** Preheating is essential in welding

**Options:**

**1)** High speed steel

**2)** Cast Iron

**3)** All non-ferrous materials

**4)** None of these

**Answer:** Cast iron

**Q 55:** The melting point is the lowest for

**Options:**

**1)** Low carbon steel

**2)** High carbon steel

**3)** Cast iron

**4)** Wrought iron

**Answer:** Cast iron

**Q 56:** ______is commonly used for making household utensils.

**Options:**

**1)** Duralumin

**2)** Hindalium

**3)** Y-alloy

**4)** Magnallium

**Answer:** Magnallium

**Q 57:** Ball bearings are generally made up of

**Options:**

**1)** Carbon steel

**2)** Carbon chrome steel

**3)** Stainless steel

**4)** Grey cast iron

**Answer:** Carbon chrome steel

**Q 58:** _____has high tendency to get work hardened.

**Options:**

**1)** Lead

**2)** Aluminium

**3)** Brass

**4)** Silver

**Answer:** Lead

**Q 59:** _______is the hardest known material

**Options:**

**1)** Cemented carbide

**2)** Ceramic

**3)** Diamond

**4)** Alloy steel

**Answer:** Diamond

**Q 60:** ________is obtained by isothermal hardening operation.

**Options:**

**1)** Cementite

**2)** Sorbite

**3)** Acicular troostite

**4)** Bainite

**Answer:** Acicular troostite

**Q 61:** Fluid is a substance which offers no resistance to change of

**Options:**

**1)** Pressure

**2)** Flow

**3)** Shape

**4)** Volume

**Answer:** Shape

**Q 62:** Density of water is maximum at

**Options:**

**1)** 0^{o}C

**2)** 0^{o}K

**3)** 4^{o}C

**4)** 100^{o}C

**Answer:** 4^{o}C

**Q 63:** A perfect gas

**Options:**

**1)** Has constant viscosity

**2)** Has zero viscosity

**3)** Is incompressible

**4)** None of these

**Answer:** None of these

**Q 64:** A fluid in equilibrium can’t sustain

**Options:**

**1)** Tensile stress

**2)** Compressive stress

**3)** Shear stress

**4)** Bending stress

**Answer:** Shear stress

**Q 65:** For manometer, a better liquid combination is one having

**Options:**

**1)** Higher surface tension

**2)** Lower Surface tension

**3)** Surface tension is no criterion

**4)** High density and Viscosity

**Answer:** Higher surface tension

**Q 66:** The resultant upward pressure of the fluid on an Immersed body is called

**Options:**

**1)** Upthrust

**2)** Buoyancy

**3)** Centre of pressure

**4)** None of these

**Answer:** Buoyancy

**Q 67:** V = 0.0022*t* – (1.8 / *t* ) is the equation to determine kinetic viscosity of liquids by

**Options:**

**1)** Redwood Viscometer

**2)** Engler Viscometer

**3)** Saybolt universal viscometer

**4)** Newton Viscometer

**Answer:** Saybolt universal viscometer

**Q 68:** The capiliary rise at 20 degree Celsius in a clean glass tube of 1 mm bore containing water is approximately

**Options:**

**1)** 3 mm

**2)** 5 mm

**3)** 10 mm

**4)** 30 mm

**Answer:** 30 mm

**Q 69:** The rise or depression of liquid in a tube to surface tension with increase in size of tube will

**Options:**

**1)** Increase

**2)** Remain unaffected

**3)** May increase or decrease depending on the characteristics of liquid

**4)** Decrease

**Answer:** Decrease

**Q 70:** In an Isothermal atmosphere the pressure

**Options:**

**1)** Decreases linearly with elevation

**2)** Remains constant

**3)** Varies in the same way as the density

**4)** Increases exponentially with elevation

**Answer:** Varies in the same way as the density

**Q 71;** The magnitude of rise of pressure due to water hammer in a rigid and non-eleastic pipe carrying water of density ρ and bulk modules **k **will be equal to

**A)**k / √ρ**B)**√kρ**C)**√(ρ / k)**D)**k / ρ

**Options:**

**1) **A Only

**2)** B Only

**3)** C Only

**4)** D Only

**Answer:** A Only

**Q 72:** The flow of any fluid, real or ideal, must fulfil the following

**Options:**

**1)** Newton’s law of viscosity

**2)** Newton’s second law of viscosity

**3)** Velocity at boundary must be zero relative to the boundary

**4)** The continuity equation

**Answer:** The continuity equation

**Q 73:** The most economical section of circular channel for maximum discharge is obtained when (Where, d is the diameter of circular section)

**Options:**

**1)** Depth of water = 0.95 d

**2)** Wetter perimeter = 2.5 d

**3)** Hydraulic mean depth = 0.29 d

**4)** Any one of these

**Answer:** Any one of these

**Q 74:** Borda’s mouthpiece is

**Options:**

**1)** A short cylindrical tube projecting inward having length of **1/2** diameter

**2)** A convergent tube having length of 2 – 3 diameters

**3)** Most commonly used

**4)** Rarely used

**Answer:** A short cylindrical tube projecting inward having length of **1/2** diameter

**Q 75: **The critical velocity as

**Options:**

**1)** Maximum

**2)** Terminal velocity

**3)** Velocity when hydraulic jump occurs

**4)** Velocity above which the flow ceases to be streamlined

**Answer:** Velocity above which the flow ceases to be streamlined

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**Q 76:** Reynolds number for non-circular cross section is:

[ V = mean velocity

v = kinematic viscosity

P = Ratio of cross sectional area to the wetter perimeter]

**A)**VAP / v**B)**P / v**C)**2P / 4v**D)**P / 4v

**Options:**

**1)** Only A

**2)** Only B

**3)** Only C

**4)** Only D

**Answer:** Only A

**Q 77:** In case of a two dimensional flow the components of velocity are given by u = ax; v = by, the streamlines will consist of a series of

**Options:**

**1)** Circular arcs

**2)** Parabolic arcs

**3)** Hyperbolic arcs

**4)** Elliptical arcs

**Answer:** Hyperbolic arcs

**Q 78:** Friction factor of pipes depends on

**Options:**

**1)** Rate of flow

**2)** Fluid density

**3)** Viscosity

**4)** All options are correct

**Answer:** All options are correct

**Q 79:** Time of floe from one tank in which water level is h_{1} to another tank having level h_{2} will be proportional to

**A)**h_{1}– h_{2}**B)**√(h_{1}– h_{2})**C)**√h_{1}– √h_{2}**D)**h_{1}^{3/2}– h_{2}^{3/2}

**Options:**

**1) **Only A

**2)** Only B

**3)** Only C

**4)** Only D

**Answer:** Only D

**Q 80:** Which of the following represents steady uniform flow ?

**Options:**

**1)** Flow through an expending tube at an increasing rate

**2)** Flow through an expending tube at constant rate

**3)** Flow through a long pipe at decreasing rate

**4)** Flow through a long pipe at constant rate

**Answer:** Flow through a long pipe at constant rate

**Q 81:** Chezy’s equation is used to determine

**Options:**

**1)** Velocity of flow in open channel

**2)** Velocity of flow in pipe

**3)** Flow over weirs

**4)** Discharge through notch

**Answer:** Velocity of flow in open channel

**Q 82:** Bluff body is the body of such a shape that pressure drag as compared to friction drag is

**Options:**

**1)** Same

**2)** More

**3)** Less

**4)** Zero

**Answer:** More

**Q 83:** For best hydraulic rectangular cross-section of an open channel, its depth should be equal to

**Options:**

**1)** Width

**2)** Two times the width

**3)** Half of the width

**4)** Three-eighth of the width

**Answer:** Half of the width

**Q 84:** The value of coefficient of velocity for a sharp edged orifice is of the order of

**Options:**

**1)** 0.45

**2)** 0.5

**3)** 0.62

**4)** None of these

**Answer:** None of these

**Q 85:** The discharge over a sharp-edged rectangular notch of width w depth h is equal to

**A)**(2/3)C_{d}w√(2gh^{5/2})**B)**(2/3)C_{d}w√(2gh)**C)**(2/3)C_{d}w√(2gh^{3/2})**D)**(8/15)C_{d}w√(2gh^{3/2})

**Options:**

**1)** Only A

**2)** Only B

**3)** Only C

**4)** Only D

**Answer:** Only C

**Q 86:** When a liquid rotates at constant angular velocity about a vertical axis as a rigid body, the pressure

**Options:**

**1)** Increases linearly as its radical distance

**2)** Varies inversely as the altitude along any vertical line

**3)** Varies as the square of the radial distance

**4)** Decreases as the square of the radial distance

**Answer:** Varies inversely as the altitude along any vertical line

**Q 87:** The discharge through a semi-circular weir is proportional

**Options:**

**1)** H^{(-1/2)}

**2)** H^{(1/2)}

**3)** H^{(3/2)}

**4)** none of these

**Answer:** None of these

**Q 88:** The rate of change of moment of momentum represents the

**Options:**

**1)** Force exerted by fluid

**2)** Torque applied by the fluid

**3)** Work done by the fluid

**4)** Power developed by the fluid

**Answer:** Torque applied by the fluid

**Q 89:** Separation of flow occurs when pressure gradient

**Options:**

**1)** Tends to approach zero

**2)** Becomes negative

**3)** Reduces to a value when vapor formation starts

**4)** None of these

**Answer:** None of these

**Q 90:** The ratio of actual discharge to theoretical discharge through an orifice is

**A)**C_{c}/ D_{d}**B)**C_{d}/ C_{v}**C)**C_{v}/ C_{d}**D)**C_{c}/ C_{v}

**Options:**

**1)** Only A

**2)** Only B

**3)** Only C

**4)** Only D

**Answer:** Only D

**Q 91:** Coke is produced by

**Options:**

**1)** Pulverizing coal in Inert atmosphere

**2)** Heating wood in a limited supply of air at temperatures below 300^{o}C

**3)** Strongly heating coal continuously for about 48 hours in the absence of air in a closed vessel

**4)** Binding the pulverized coal into briquettes.

**Answer:** Strongly heating coal continuously for about 48 hours in the absence of air in a closed vessel

**Q 92:** One kg of steam sample contains 0.8 kg dry steam; It’s dryness fraction is

**Options:**

**1)** 0.2

**2)** 0.8

**3)** 0.6

**4)** 0.5

**Answer:** 0.8

**Q 93:** At which pressure (in kg/cm^{2}) the properties of water and steam become identical

**Options:**

**1)** 0.1

**2)** 1

**3)** 100

**4)** 225.6

**Answer:** 225.6

**Q 94: **Cochran boiler is a

**Options:**

**1)** Horizontal fire-tube boiler

**2)** Horizontal water-tube boiler

**3)** Vertical water-tube boiler

**4)** Vertical fire tube boiler

**Answer:** Vertical fire tube boiler

**Q 95:** The diameter of tubes for natural circulation boiler as compared to controlled circulation boilers is

**Options:**

**1)** More

**2)** Less

**3)** Same

**4)** Could be more or less depending on other factors

**Answer:** More

**Q 96:** Supercharging is the process of

**Options:**

**1)** Supplying the Intake of an engine with air at a density greater than the density of the surrounding atmosphere

**2)** Providing forced cooling air

**3)** Injecting excess fuel for raising more load

**4)** Supplying compressed air to remove combustion products fully

**Answer:** Supplying the Intake of an engine with air at a density greater than the density of the surrounding atmosphere

**Q 97:** The accumulation of carbon in a cylinder results in Increase of

**Options:**

**1)** Clearance volume

**2)** Volumetric efficiency

**3)** Ignition time

**4)** Effective compression ratio

**Answer:** Effective compression ratio

**Q 98:** Which of the following is a false statement ? Excess quantities of Sulphur in diesel fuel are objectionable because it may cause the following

**Options:**

**1)** Piston ring and cylinder wear

**2)** Formation of hard coating on piston skirts

**3)** Oil sludge in the engine crank case

**4)** Detonation

**Answer:** Detonation

**Q 99:** Installation of supercharger on a four-cycle diesel engine can result in the following percentage increase in power

**Options:**

**1)** Upto 25%

**2)** Upto 35%

**3)** Upto 50%

**4)** None of these

**Answer:** None of these

**Q 100:** In order to prevent formation of carbon on the Injector, the temperature (In ^{o}C) of nozzle tip should be

**Options:**

**1)** Less than 100

**2)** Between 100 – 250

**3)** Between 250 – 300

**4)** Between 400 – 500

**Answer:** Between 250 – 300

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