Final ME Paper I IES 2010

7/28/2019 Final ME Paper I IES 2010

1/18

Indias No 1 IES-2010

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Q1. If a Mohr circle is drawn for a fluid element inside a fluid body at rest, it

would be

(a)A circle not touching the origin(b)A circle touching the origin(c) A point on the normal stress axis(d)A point on the shear stress axis

Q2. In a Francis turbine, the runner blades are radial at the entrance and the

discharge is radial at the outlet. For this turbine

(a) The relative velocity is radial at the outlet(b) The absolute velocity is radial at the outlet(c) The guide vane angle is 900(d) The velocity of flow is constant

Q3. A gas is being discharged isentropically from a tank of pressure p1 (abs)

through a converging nozzle in a receiving chamber of pressure p2 (abs)

with critical flow condition in the nozzle exit. Ifp2 is kept constant andp1 isdoubled, the mass rate of flow through the nozzle will

(a) Not change(b) Be doubled(c) Be halved(d) Increase by 2 times

Q4. Uniform flow in a channel is characterised by the following statement:

(a) Total energy remains constant along the channel(b) Gradient of the total energy is parallel to the channel bed(c) Specific energy decreases along the channel(d) Total energy line either rises or falls depending upon the Froude number

Q5. For a given discharge in a channel at critical depth(a) The total energy is minimum(b) The total energy is maximum(c) The specific energy is maximum(d) The specific energy is minimum

Q6. For an inclined plane submerged in a liquid the centre of fluid pressure on

one side of the plane will be:

(a)Above the top edge of the area(b)Vertically below the centre of gravity(c) Below the centre of gravity(d) In the same horizontal plane as the centre of gravity

Q7. A metal block is thrown into a deep lake. As it sinks deeper in water, the

buoyant force acting on it

(a) Increases(b) Remains the same(c) Decreases(d) First increases and then decreases


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Q8. A tank, open at top, contains a liquid with a relative density of 0.85 to a

depth of 1.2 m. The acceleration which should be given to the tank to make

the pressure at the bottom atmospheric is

(a) 9.8 m/s2 vertically upward(b) 9.8 m/s2 vertically downward(c) 8.33 m/s2 vertically upward(d) 8.33 m/s2 vertically downward

Q9. In a circular pipe of certain length carrying oil at a Reynolds number 100, it

is proposed to triple the discharge. If the viscosity remains unchanged, the

power input will have to be

(a) Decreased to 1/3 its original value(b) Increased by 100%(c) Increased to 3 times the original value(d) Increased to 9 times its original value

Q10. Bernoulli equation is applicable between any two points

(a) In any rotational flow of an incompressible fluid(b) In any type of irrotational flow of a fluid(c) In steady rotational flow of an incompressible fluid(d) In steady, irrotational flow of an incompressible fluid

Q11. The speed of sound in air varies as

(a) T (b) (c) 1P

(d) p

where T= absolute temperature, = density and p = absolute pressure

Q12. The water level in a cylindrical tank with its axis vertical was lowered from

an elevation of 4 m to 2.0 m in 200 s by discharging the contents through an

orifice at the bottom of the tank. If the diameter of the orifice is doubled,the time required for the above lowering of the water surface would be:

(a) 50 s (b) 100 s (c) 12.5 s (d) 200 s

Q13. A two-dimensional flow in xy plane is rotational, if

(a)u v

x y

=

(b)

u u

x y

=

(c)

v u

x y

=

(d)

v v

x y

=

Q14. A battery is used to light a bulb, run a fan and heat an electric iron in case

of a power failure. If each of the above systems has 100 W rating and is run

for 15 minutes, what are the work done (W) and heat transferred (Q) by the

battery?

(a) W = 90 kJ and Q = 90 kJ (b) W = 180 kJ and Q = 0(c) W = 270 kJ and Q = 0 (d) W = 90 kJ and Q = 180 kJ

Q15. A reversible engine exchanges heat from three thermal reservoirs A, B and

C at 1000 K, 800 K and 200 K respectively. If the engine receives 500 kJ from

A and 400 kJ from B then what is the heat exchanged from thermal

reservoir C?

(a) 450 kJ rejected to thermal reservoir C


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(b) 350 kJ rejected to thermal reservoir C

(c) 250 kJ rejected to thermal reservoir C

(d) 200 kJ rejected to thermal reservoir C

Q16. A 100 resistor carrying a constant current of 0.5 A is kept at a constanttemperature of 300 K by a stream of cooling water. In a time interval of 30

minutes, what are the changes in entropy for the resistor and that of the

universe, respectively?

(a) 0 and 150 J/K (b) 150 J/K and 0 (c) 300 J/K and 0 (d) 0 and 300 J/K

Q17. A system of 100 kg mass undergoes a process in which its specific entropy

increases from 0.30 kJ/kg K to 0.35 kJ/kg K. At the same time, the entropy of

the surroundings decreases from 80 kJ/K to 75 kJ/K. What is the type of this

process?

(a) Reversible (b) Irreversible

(c) Impossible (d) Not identifiable with the date given

Q18. Two reversible engines are working in series between a high temperature

reservoir at 1000 K and a low temperature reservoir at 300 K is such a way

that the heat rejected by the preceding engine is completely absorbed by

the succeeding engine and both the engines develop the same amount of

work per cycle. What is the intermediate temperature between first and

second engines?

(a) 700 K (b) 650 K

(c) 350 K (d) Not possible to be estimated with the given date

Q19. An Electrolux system of refrigeration has

(a) No liquid pump (b) One liquid pump

(c) Two liquid pumps (d) Three liquid pumps

Q20. When the lower temperature is fixed, how can the COP of a refrigerating

machine be improved?

(a) By raising the higher temperature

(b) By lowering the higher temperature

(c) By operating the machine at higher speeds

(d) By operating the machine at lower speeds

Q21. What is/are the effect(s) of super saturation in nozzle flow?

(1) It increases the mass flow

(2) It increases friction in the nozzle

(3) It increases exit velocity

(4) It reduces dryness fraction of steam

Select the correct answer using the code given below(a) 1 only (b) 1 and 3 (c) 1, 2 and 4 (d) 3 only

Q22. Consider the following statements A tube section diverging in the direction

of fluid flow can be used as

(1) Supersonic nozzle (2) Subsonic nozzle

(3) Supersonic diffuser (4) Subsonic diffuser


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Which of the statements given above is/are correct?

(a) 1 only (b) 1 and 4 (c) 3 only (d) 2 and 3

Q23. Consider the following statements:

(1) Fusible plug is a device used to put off fire in the furnace of the boilerwhen the level of water in the boiler falls to an unsafe limit.

(2) Super heater is a device used to increase the temperature of saturated

steam without raising its pressure.

(3) An economizer decreases the steam raising capacity of boiler. Which of

the above statements is/are correct?

(a) 1 and 2 (b) 2 and 3 (c) 1 only (d) 1, 2, and 3

Q24. What is the cause of reheat factor in a steam turbine?

(a) Reheating (b) Superheating

(c) Super saturation (d) Blade friction

Q25. If u = ax and v = -ay give the velocity distribution for a two dimensional

flow, what is the equation of a stream line passing through the point (3, 1)?

(a) xy = 3 (b) x + y = 4 (c) x + 3y = 6 (d) x2y = 9

Q26. Consider the following statements pertaining to Room Sensible Heat Ratio

(RSHR) line

(1) It is the line drawn on psychometric chart through the room conditions.

(2) Its slope is the ratio of sensible cooling load to room latent heat load.

(3) The supply air condition must lie on this line for satisfactory

performance.

Which of the statements given above are correct?

(a) 1, 2 and 3 (b) 1 and 2 (c) 1 and 3 (d) 2 and 3

Q27. When 40C and 25C are the dry bulb temperatures of air entering andleaving a cooling coil, then the cooling coil temperature is 25C. What is the

bypass factor for the case of sensible cooling?

(a) 0.20 (b) 0.25 (c) 0.50 (d) 0.60

Q28. A water chiller with a capacity of 30 tons of refrigeration cools 20 m3/hr of

water entering at 12C. What is the temperature of water leaving the

chiller?

(a) 5C (b) 6C (c) 7C (d) 7.5C

Q29. Why is enriched Uranium required as fuel when ordinary water is used as a

moderator?

(a) Ordinary water has low moderating efficiency

(b) Ordinary water has high neutron absorption(c) Ordinary water has high moderating efficiency

(d) Ordinary water has low neutron absorption

Q30. Which one of the following gases is normally not used as a coolant in

nuclear reactor?

(a) Hydrogen (b) Helium (c) Carbon dioxide (d) Nitrogen


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Q31. Match List-I with List-II and select the correct answer using the code given

below the list:

List-I

A. Draft tube

B. SurgingC.Air Vessel

D. Nozzle

List-II

1. Impulse turbine

2. Reciprocating pump3. Reaction turbine

4. Centrifugal pump

Codes:

A B C D A B C D

(a) 1 2 4 3 (b) 3 4 2 1

(c) 1 4 2 3 (d) 3 2 4 1

Q32. Match List-I with List-II and select the correct answer using the code given

below the list:

List-I (Name of Boiler)

A. Stirling

B. Cochran

C. Lancashire

D. Benson

List-II (Type)

1. Bent water tube

2. Once through flow

3.Vertical fire tube

4. Incline water tube

5. Horizontal fire tube

Codes:

A B C D A B C D

(a) 2 5 4 1 (b) 1 3 5 2

(c) 2 3 5 1 (d) 1 5 4 2

Q33. In a steam power plant, what is the outcome of regenerative feed heating?

1. Increase in specific output

2. Increase in cycle efficiency

3. Improved quality of exhaust steam

4. Reduced condenser loadSelect the correct answer using the code given below

(a) 1 and 3 only (b) 2 only (c) 2 and 4 (d) 1, 2 and 3

Q34. Consider the following statements in the context of high pressure boilers:

1. The tendency of scale formation is eliminated due to high velocity of

water through tubes.

2. The heat transfer coefficient is increased by increasing the velocity of

water through tubes.

3. The steam can be raised quickly to meet the variable load.


(a) 1 and 2 only (b) 2 and 3 only (c) 1 and 3 only (d) 1, 2 and 3

Q35. Which one of the following is the shock that occurs for an airplane travelingat supersonic speed?

(a) Normal shock (b) Oblique shock

(c) Bow shock (d) Air shock

Q36. Which one of the following is the correct statement?

In a two-stage gas turbine plant with inter-cooling and reheating

(a) Both work ratio and thermal efficiency improve


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(b) Work ratio improves but thermal efficiency decreases

(c) Thermal efficiency improves but work ratio decreases

(d) Both work ratio and thermal efficiency decrease

Q37. Consider the following statements1. Boundary-layer thickness in laminar flow is greater than that of

turbulent flow.

2. Boundary-layer thickness of turbulent flow is greater than that of

laminar flow.

3. Velocity distributes uniformly in a turbulent boundary layer.

4. Velocity has a gradual variation in a laminar boundary layer.


(a) 1, 3 and 4 only (b) 1, 2, 3 and 4

(c) 1 and 2 only (d) 2, 3 and 4 only


The velocity profiles for fully developed laminar and turbulent flow,

respectively, in a pipe are:

(a) Parabolic and parabolic (b) Parabolic and elliptic

(c) Linear and 1/7 power law (d) Parabolic and 1/7 power law


For the case of laminar flow between two fixed parallel plates, the shear

stress is:

(a) Constant across the passage

(b) Maximum at the centre and zero at the boundary

(c) Zero all through the passage

(d) Maximum at the boundary and zero at the centre

Q40. Consider the following statements:The coefficient of discharge Cd of a venturimeter takes into account

1. The effect of roughness of the surface

2. Non-uniform velocity distributions at inlet and throat section

3. Reynolds number of flow

4. Discharge

5. Length of throat

6. Diameter of throat

7. Diameter ratio


(a) 1, 2, 4 and 5 (b) 1, 2, 3 and 7

(c) 1, 4, 5 and 6 (d) 2, 6 and 7

Q41. Which of the following is the correct statement?A differential manometer connected to a pitot-static tube used for

measuring fluid velocity gives

(a) Static pressure

(b) Total pressure

(c) Dynamic pressure

(d) Difference between total pressure and dynamic pressure


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Q42. Which one of the following correctly represents the shear stress

distribution across a section of a circular pipe having a viscous flow?

(a)

2pr

x

=

(b)( / 2)p r

x

=

(c)( / 2)p r

x

=

(d)( )p r

x

=

Q43. Match List-I (Forms of Bernoullis Equation) with List-II (Units of these

forms) and select the correct answer using the code given below the lists:

List-I

A.

2

2

pVp wz+

B.

2

2

p Vgz

p+ +

C.

2

2

p Vz

w g+ +

List-II

1. Total energy per unit volume

2. Total energy per unit mass

3. Total energy per unit weight

Codes:

A B C A B C

(a) 1 2 3 (b) 1 3 2

(c) 2 1 3 (d) 2 3 1


A frictionless, incompressible fluid flows steadily through a convergent

nozzle, then its

(a) Energy must decrease (b) Velocity must decrease

(c) Pressure must decrease (d) Momentum must decrease

Q45. Which one of the following statements is correct?For stability of a floating body,

(a) M should lie between G and B (in that order)

(b) M should lie above B and G (in that order)

(c) M should lie below B and G (in that order)

(d) M should coincide with B and G


A rectangular block of wood of size L B H will float in water in such a way

that

1. The longest dimension is vertical

2. The longest dimension is horizontal

3. The mctacentre is above the centre of gravity

4. The centre of buoyancy is above the centre of gravityWhich of the statements given above are correct?

(a) 1 only (b) 2 and 3 only

(c) 2, 3 and 4 (d) 1, 3 and 4

Q47. What are the properties of a thermodynamic system, whose value for the

entire system is equal to the sum of their values for individual parts of the

system?


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(a) Thermodynamic properties (b) Extensive properties

(c) Intensive properties (d) None of the above

Q48. A new temperature scale in degrees N is to be defined. The boiling and

freezing point of water on this scale are o400 N and o100 N respectively.

What will be the reading on new scale corresponding too60 C ?

(a) 110N (b) 180N (c) 210N (d) 280N

Q49. Which thermometer is independent of the substance or material used in its

construction?

(a) Memory thermometer (b) Alcohol thermometer

(c) Ideal gas thermometer (d) Resistance thermometer

Q50. A closed system undergoes a process during which 150 kJ of heat is added

to it. The system is then restored in its initial state. If the heat transfer and

work transfer for the second process are 50 kJ and + 75 kJ respectively,

what is the work transfer for the first process?(a) 25 Kj (b) 50 kJ (c) 75 kJ (d) 100 kJ

Q51. A heat engine working in a thermodynamic cycle draws 500 kJ of heat

energy from a source of 1000 K per cycle and rejects certain amount of heat

energy at 300 K per cycle. Then, which one of the following is correct?

(a) The amount of heat energy rejected must be 150 kJ

(b) The amount of heat energy rejected must be less than 150 kJ

(c) The amount of heat energy rejected must be greater than 150 kJ

(d) It is not possible to make any statements regarding the amount of heat energy

rejected per cycle from the data given

Q52. The thermal efficiency of the Carnot engine is 0.5. If the engine is operated

as refrigerator, what is the C.O.R of the refrigerator?

(a) 0.5 (b) 1.0 (c) 2.0 (d) 25

Q53. Which one of the following is correct?

De Laval turbine is a

(a) Simple reaction turbine

(b) Simple impulse turbine

(c) Velocity compounded impulse turbine

(d) Pressure compounded impulse turbine


Reheating of steam under ideal conditions takes place t constant

(a) Entropy (b) Enthalpy (c) Pressure (d) Temperature

Q55. Consider the following statement s about reactors:

1. CANDU reactor is natural uranium fuelled, heavy water cooled and

moderated reactor.

2. In a pressurized water reactor the coolant water boils in the core of the

reactor.

3. Liquid metal is preferred as a coolant in case of a homogencous reactor.


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4. Which of the statements given above is/are correct?

(a) 1 only (b) 2 only (c) 1 and 3 only (d) 1, 2 and 3

Q56. What is the material of thick walled canisters in which nuclear waste is

buried deep?(a) Zirconium (b) Lead (c) Stainless steel (d) Tin

Q57. Consider the following refrigerants:

1. Ammonia

2. Carbon dioxide

3. Dichlorodifluoro methane

4. Tetrafluoromethane

Which one of the following is the correct order of their boiling points in the

descending order?

(a) 1 2 3 4 (b) 2 3 4 1

(c) 3 1 2 4 (d) 2 4 1 3

Q58. Where is an oil separator in vapour compression refrigeration system

installed?

(a) Between compressor and condenser

(b) Between expansion value and receiver tank

(c) Inside compressor machinery

(d) Outside compressor machinery

Q59. Which one eco-friendly refrigerant out of the following is used in many

domestic and car air-conditioners nowadays?

(a) R-22 (b) R-113 (c) R-123 (d) R-134a


Sensible heating of moist air will not affect the(a) Relative humidity (b) Absolute humidity

(c) Specific humidity (d) Wet bulb temperature

Q61. Which one of the following is the correct statement? When moist air passes

through a cooling tower the process is.

(a) Evaporative cooling (b) Adiabatic saturation

(c) Cooling and dehumidification (d) Heating and humidification


During sensible cooling process for a moist air,

(a) Specific humidity will decrease (b) Specific humidity will increase

(c) Relative humidity will decrease (d) Relative humidity will increase

Q63. During a comfort air conditioning process, the moisture content of the air

may start decreasing.

Which one of the following is correct statement?

In order to maintain the same level of comfort,

(a) WBT should be decreased (b) DBT should be increased

(c) Air velocity should be decreased (d) Moisture content should be increased


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Q64. The comfort air conditioning can be obtained by innumerable combinations

of DBT and relative humidity. Which one the following combinations within

the comfort zone recommended to save the energy?

(a) Higher DBT and lower relative humidity

(b) Lower DBT and lower relative humidity

(c) Lower DBT and higher relative humidity

(d) Higher DBT and higher relative humidity

Q65. Bernoullis equation is derived by making which one of the following

assumptions?

(a) The flow is steady only

(b) The flow is uniform and incompressible

(c) The flow is non-viscous, uniform and steady

(d) The flow is steady, non-viscous incompressible and irrigational

Q66. What is the rate of heat interchange per unit change of volume for a

polytropic process?

?pn

v

CpV C

C

= =

(a)1

1

np

(b)

1

np

(c)

1

np

n

(d)

1np

n

Q67. What is the value of n in an adiabatic expansionnpV = constant? (no heat

is supplied or rejected to the surroundings)

p

v

CC

(a) (b) / 2 (c) / 6 (d) /3

Q68. For an ideal gas, R = 0264 kJ/kg K, = 118 and heat transfer is 160 kJ.

What is the value of pC ?

(a) 1.53 (b) 1.62 (c) 1.73 (d) Cannot be determined with the given data

Q69. While deriving an expression for efficiency of a Carnot cycle, which one of

the following is not a correct assumption?

(a) The cylinder head is a perfect insulator(b) Both piston and cylinder are perfect insulators

(c) The hot body has infinite capacity

(d) The cold body has infinite capacity

Q70. What is the value of triple point of water?

(a) 27316 K (b) 37316 K (c) 290.45 K (d) 312.45 K


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1. Two reversible adiabatics can never intersect each other.

2. For a thermodynamic process, 0dQ

IT

+ , where I is the measure of

irreversibility.


(a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2

Q72. A reversible engine receives heat from a reservoir at 700C and rejects heat

at a temperature 2T . A second reversible engine operating on Carnot cyclereceives heat rejected by the first engine and rejects heat to a sink at 37C.

If work output from each of the engines is equal, what is the value of

temperature 2T ?(a) 6415 K (b) 537 K (c) 516 K (d) 4985 K


1. The Second Law analysis can be applied to thermodynamic cycles only

and not to individual processes.

2. The Second Law analysis clearly gives an idea about the irreversibilities

in the heat exchangers where as no idea is obtained from the First Law

analysis.



Q74. For a compression or heating process, what is the expression for

effectiveness ?

Increase of availability of the surroundings

(a)Increase of availability of the surroundings

Loss of availability of the system =

(b)Increase of availability of the system

Lossof availability of the surroundings =

(c)Loss of availability of the surroundings

Increase of availability of the system =

(d)Loss of availability of the system

Increase of availability of the surroundings =


1. Induced draught fans require water cooled bearings.

2. For an induced draught fan installation, the fan size and power

requirements are less than those of a forced draught fan installation.




13/18






1. In a steam power plant, the volume flow at the low pressure end is

considerably reduced by bleeding.

2. Theoretically, the efficiency of a steam power plant increases with the

increasing number of feed heaters but the gain is in diminishing return.Which of the statements given above is/are correct?



1. Reheating in a steam power plant leads to increased condenser

requirement.

2. The efficiency of regenerative cycle in a steam power plant is maximum

when the temperature of bled steam is equal to the geometric mean of

the extreme temperatures of the primary flow cycle.



Q78. Which of the following are the advantages of a surface condenser?

1. Less quantity of make up water is required.

2. It is suitable for higher capacity plants.

3. Power requirements of circulating pump and air pump are much less.

Select the correct answer using the code given below:

(a) 1 and 2 only (b) 2 and 3 only (c) 1 and 3 only (d) 1, 2 and3


For a single-stage water cooled air compressor,

1. The volumetric efficiency decreases as the pressure ratio is increased.

2. Shaft power /3m/ min of free air increases as the pressure ratio is

increased.

Which of the statements given above is/are correct?(a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2

Q80. Consider the following statements in respect of an S.I. engine:

1. The maximum speed occurs when the fuel mixture is about 10% richer

than the stoichiometric value.

2. An increase in compression ratio decreases the flame speed.

3. An increase in intake temperature increases the flame speed.



Q81. Which one of the following is not correctly matched as a measure to be

taken to reduce detonation in an S.I. engine?

Variable Measure(a) Spark timing Retard

(b) Engine speed Increase

(c) Intake pressure Increase

(d) Combustion chamber shape Make compact

Q82. Consider the following statements in respect of a C.I. engine:

1. An increase in compression ratio reduces the delay period.


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2. An increase in injection advance angle increases the delay period.

3. An increase in jacket water temperature reduces delay period.




1. The fuel of cetane number 40 has the same ignition quality as that of a

mixture having 40% -methylnaphthalene.

2. In the cetane number testing of an unknown fuel, the engine is first run

on the test fuel with injection timing set at 3 before the TDC.




1. In a nozzle, if the fluid velocity is greater than the local sound velocity,

the duct must converge.

2. In a diffuser, if the fluid velocity is greater than the local sound velocity,

then the duct must diverge.



Q85. For a convergent nozzle, what is the correct expression for the critical

pressure, if the inlet pressure is 1p ?

(a)

/ 1

1

2p

1

+ (b)

/ 1

1

1p

2

+

(c)

1/

1

2p

1

+ (d)

2 / 1

1

1p

2

+

Q86. The COP of a refrigerator working on a reversed Carnot cycle is 5. What is

the ratio of the absolute condenser and evaporator temperatures?

(a) 1.2 (b) 1.25 (c) 130 (d) 135

Q87. The enthalpy of steam entering a turbine in a Rankine cycle is 3200 kJ/kg.

The enthalpy after isentropic expansion is 2400 kJ/kg and the enthalpy at

the end of actual expansion is 2560 kJ/kg. What is the turbine efficiency?

(a) 75% (b) 80% (c) 85% (d) 90%

Q88. What is the ratio of the slopes for p-v curves for an adiabatic process and an

isothermal process?

(a) 1/

(b) + 1 (c) (d)1

1 +

Q89. What is the molecular weight (approximate) for the gas whose specific heatsare as follows?

pC = 1967 kJ/kg K

vC = 1507 kJ/kg K

(a) 17 (b) 18 (c) 19 (d) 20


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Q90. For a Carnot engine 1T > 2T . When 2T is decreased by T with 1T remaining

same then efficiency is 1 , and when 1T is increased by T with 2T

remaining same, efficiency is 2 . Which one of the following is the correct

expression for ( 1 - 2 )?

(a)

22 1

2 2

( ) ( )

( )

T T T T

T T T

+

+ (b)

22 1

1 1

( ) ( )

( )

T T T T

T T T

+

+

(c)

21 2

1 1

( ) ( )

( )

T T T T

T T T

+

+ (d)

21 2

1 1

( ) ( )

( )

T T T T

T T T

+ +

+

Q91. What is the value of slope for an isothermal process on p-v diagram for an

ideal gas?

(a) - p/v (b) - v / p (c) - 1 / (pv) (d) pv

Q92. A gas turbine cycle with infinitely large number of stages during

compression and expansion leads to which one of the following?(a) Stirling cycle (b) Atkinson cycle

(c) Ericsson cycle (d) Brayton cycle

Q93. A section diverging in the direction of flow can be used as which of the

following?

1. Subsonic nozzle 2. Supersonic nozzle

3. Subsonic diffuser 4. Supersonic diffuser

Select the correct answer using the code given below:

(a) 1 only (b) 2 and 3 (c) 1 and 4 (d) 3 only

Q94. A Pelton wheel operates with a speed of 600 rpm, speed ratio of 044 and a

net head of 300 m. What is the diameter of the wheel?

(a) 0.32 m (b) 1.07 m (c) 1.51 m (d) 2.14 m

Q95. For a steam jet angle of 30 (from the tangential direction) at the entrance,

what is the maximum blade efficiency (approximate) of a Parson's turbine?

(a) 085 (b) 049 (c) 04 (d) 0'3

Q96. Which is the most susceptible place for cavitation in a hydraulic turbine?

(a) Penstock (b) Blade inlet

(c) Guide blade (d) Inlet to draft tube

Q97. How is specific speed sN of a hydraulic turbine defined as? (N = speed, P =

power, Q = discharge, H = head)

(a) sN = 1/2NP / 3/4H (b) sN = 1/2NQ / 3/4H

(c) sN =1/2NP / 5/4H (d) sN =

1/2NQ / 5H

Q98. In a reaction turbine enthalpy drop per stage is 60 units while the enthalpy

drop in the moving blade is 32 units. What is the degree of reaction?

(a) 028 (b) 0.46 (c) 053 (d) 187


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Q99. Where is shock effect felt in a nozzle?

(a) Divergent portion (b) Entrance

(c) Convergent portion (d) Throat

Q100. What is the value of the Mach number in the convergent portion of a steamnozzle.

(a) One (b) Zero (c) > 1 (d) < 1 ( 0)

Q101. The inlet and outlet temperatures of at flowing over a heating coil having

temperature of 41C are 15C and 28C, respectively. What is the coil

efficiency?

(a) 25% (b) 50% (c) 75% (d) 90%

Q102. The cooling loads for a building are:

RSH = 100 kW (Room sensible heat)

RLH = 25 kW (Room latent heat)

OASH = 10 kW (Outside air sensible heat)

OALH = 10 kW (Outside air latent heat)

The bypass factor of the cooling coil is 0.15. What are the values of the room

sensible heat factor and external sensible heat factor, respectively?

(a) 0.72 and 0.8 (b) 0.8 arid 0.79

(c) 0.79 and 0.8 (d) 0.79 and 0.72

Q103. Which one of the following statements is correct?

Dew point temperature of a moist air sample remains constant during

(a) A sensible heating or cooling process

(b) An adiabatic saturation process

(c) A dehumidification process

(d) A humidification process


For a cooling and dehumidification process, the moist air has to be passed

through a coil whose temperature is below the

(a) Dry-bulb temperature of the air

(b) Wet-bulb temperature of the air

(c) Dew-point temperature of the air

(d) Critical temperature of the air


For a specified condenser temperature, the coefficient of performance of a

refrigerator,

(a) Increases with the increase in the evaporator temperature

(b) Decreases with the increase in the evaporator temperature(c) Is independent of the evaporator temperature

(d) Is proportional to the square of the evaporator temperature

Q106. In a centralized air conditioning system, what is the power of a fan directly

proportional to?

(a) Fan speed (b) ( )2

Fanspeed (c) ( )3

Fan speed (d) ( )4

Fan speed


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Q107. What is the correct expression for momentum thickness ( ) in a boundary

layer?

(a) =

0

(1 )u

dy

u

(b)0

(1 )u u

dy

u u

=

(c)

2

2

0

(1 )u u

dyu u

= (d)2

2

0

(1 )u u

dyu u

=

Q108. What causes flow separation in flow past a solid object?

(a) Reduction of pressure to vapour pressure

(b) A negative pressure gradient

(c) A positive pressure gradient

(d) The boundary layer thickness reducing to zero

Q109. The rate of flow through a V-notch is proportional to which one of the

following?

(a) H (b) 1/2H (c) 3/2H (d) 5/2H


Darcy's friction factor and Fanning friction factor for flow in a circular

duct

(a) Are equal

(b) The former is a non-dimensional wall shear stress

(c) The latter is a non-dimensional wall shear stress

(d) The former is one fourth of latter


In a fully developed flow through a pipe

(a) The velocity profile is parabolic(b) The shear stress is constant over the section

(c) The pressure changes linearly with distance

(d) The momentum correction factor is zero


The Euler's equation for fluid flow refers to motion with

(a) Constant velocity (b) Acceleration along the flow

(c) Retardation along the flow (d) Constant acceleration

Q113. Which one of the following is the continuity equation in differential form?

(a) AdA + AdV + d = 0 (b) 0dA dV d

A V

+ + =

(c)dA dV d

A V

+ + = Constant (d) AdA + VdV + d = Constant

Q114. What is the depth of the centre of pressure in a rectangular lamina

immersed vertically in water upto a depth h?

(a) h/4 (b) h/2 (c) 2h/3 (d) h/3


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25 1st Floor Jia Sarai Near IIT New Delhi 16 Ph: 011 26537570 9810958290

Q115. Which one of the following statements is correct?According to Bernoulli's equation for steady ideal fluid flow,(a) Total energy is constant throughout(b) Principle of conservation of mass holds

(c) Velocity and pressure are inversely proportional(d) The energy is constant along a stream line but may vary across stream lines

Q116. Assertion (A):In turbulent flow through a commercial concrete pipe, thefriction factor is practically independent of Reynolds number .but dependson the surface roughness.Reason (R):In a commercial pipe, pressure drop is primarily governed byflow separation at the roughness length scales of the wall.(a) Both A and R are individually true and R is the correct explanation of A(b) Both A and R are individually true but R is NOT the correct explanation of A(c) A is true but R is false(d) A is false but R is true

Q117. Assertion (A): Refrigerants R11 and R12 have a greater impact on ozonedepletion than R22.Reason (R): R22 has a larger number of chlorine atoms.(a) Both A and R are individually true and R is the correct explanation of A(b) Both A and R are individually true but R is not the correct explanation of A(c) A is true but R is false(d) A is false but R is true

Q118. Assertion (A): The coefficient of discharge of a venturimeter is higher thanthat of an orifice meter.Reason (R): Orifice meter produces eddies and crosscurrents in the fluidfloe, which dissipate energy.(a) Both A and R are individually true and R is the correct explanation of A.(b) Both A and R are individually true but R is NOT the correct explanation of A.

(c) A is true But R is false(d) A is false but R is true

Q119. Assertion (A): A thermo-dynamic cycle that violates the Clausius inequalityalso violates the second law of thermodynamics.Reason (R): The Clausius inequality is given by

0Q

T

v .

(a) Both A and R are individually true and R is the correct explanation of A(b) Both A and R are individually true but R is NOT the correct explanation of A(c) A is true but R is false(d) A is false but R is true

Q120. Assertion (A): The deviation of a gas from ideal gas behaviour is least in thevicinity of the critical point.Reason (R): The compressibility factor for all gases is approximately thesame at the same reduced pressure and temperature.(a) Both A and R are individually true and R is the correct explanation of A(b) Both A and R are individually true but R is NOT the correct explanation of A(c) A is true but R is false (d) A is false but R is true

Final ME Paper I IES 2010

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