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S.No Question Option A Option B Option C Option D Answer Solution Comments Status Action
1 Which of the following turbine has 50% degree of reaction? Rateau turbine Hero’s Turbine Parson’s turbine Curtis turbine c   Degree of reaction = \(\frac{enthalpy drop in moving blade}{total enthalpy drop}\)
It is define for reaction turbine only.
For impulse turbine R=0
For Parson's turbine or 50% reaction turbine R = 0.5
100% Reaction turbine – Hero’s turbine		 Comments Active
2 Which of the following statements holds true, according to Kelvin Planck’s statement? A heat engine must exchange heat from a single heat reservoir. Perpetual motion machine of the 2nd kind is impossible. Some amount of heat taken from a source must be rejected to a higher temperature sink. It restricts the engine to have mechanical efficiency lesser than unity. b Kelvin-Planck statement: It is impossible for a system to accept a given amount of heat from a high-temperature medium and to deliver an equal amount of work output, meaning that a heat engine cannot have a thermal efficiency of 100%. Comments Active
3 A closed vessel contains 5 kg of air, and 50 kJ of heat is given to it. If 75 kJ of work is done by the system, then which of the following is true?(Take Cp = 1.005 kJ/kg-K, Cv = 0.718 kJ/kg-K) The temperature of air aill decrease by 34.8o The temperature of air will increase by 5o The temperature of the air will increase by 7o The temperature of the air will decrease by 7o d
Vessel is closed means constant volume,
\(∂Q=∆U+∂W,\)
\( 50=∆U+75, \)
\( ∆U=mc∆T\)
\(-25=5×0.718×∆T, \)
\(∆T=-6.96=-7, \)
The temperature of the air will decrease by 7 \(°\)		 Comments Active
4 In aqua-ammonia absorption refrigeration system, incomplete rectification leads to accumulation of water in: Heat exchanger Condenser Evaporator Absorber b Ammonia is the refrigerant while water is used as absorbent. The absorber absorbs the low pressure ammonia vapour coming from evaporator. The cold water in absorber has the ability to absorb very large quantities of ammonia vapour and the solution formed is called 'aqua-ammonia'. In aqua-ammonia absorption refrigeration system, incomplete rectification leads to accumulation of water in condenser. Comments Active
5 Which of the following point angles of a twist drill is used for general purpose work? 128° 118° 138° 108° b • Drilling is the production of cylindrical holes of definite diameters in workpieces by using a multi-point cutting tool called a 'drill'.
• The point angle of a twist drill is the angle made by the cutting lip and the axis of the drill.
• For general purpose drilling, a point angle of 118° is recommended.		 Comments Active
6 Which of the following is a suitable unit for measuring the capacity of refrigeration? Kg kJ Kw/kg TR d unit for measuring the capacity of refrigeration
1 TR = 3.5 KW or = 210 = 1400 \(\frac{kJ}{sec}\) \(\frac{kJ}{min}\) \(\frac{kJ}{hr}\)
1 TR: One ton of refrigeration is defined as the capacity to freeze one tone of water at 0°C into ice in 24 hours.		 Comments Active
7 What will be the specific weight of one litre of petrol of specific gravity 0.7? (Take g = 9.81 m/sec2) 5436 N/m3 6256 N/m3 7286 N/m3 6867 N/m3 d Given
\(δ_{p}=0.7\)
\(δ_{w} of water=9.81\)
\(V=1l=10^{-3}m^{3}\)
\(δ_{w} of material=?\)
\(Specific gravity=\frac{Specific weight of petrol}{Specific weight of water}\)
\(0.7=\frac{δ_{w}of petrol}{9.81}\)
\(δ_{w}of petrol=0.7×9.81\)
\(=6.867 KN/m^{3}\)
\(δ_{w}of petrol=6867 N/m^{3}\)		 Comments Active
8 Which of the following equations is used to calculate major losses in pipes? Continuity equation Momentum equation Reynolds’s equation Darcy-Weisbach equation d As we know that head loss due to friction (that is major loss in pipe) is calculated by the following darcy weisbach formula,
, \(h_{f}=\frac{4flV^{2}}{2gd}\)
f=Darcy’s coefficient of friction, l=length of the pipe, v=velocity of the fluid in the pipe, d= diameter of pipe		 Comments Active
9 Which of the following statements is true about hot working process? Hot working process of tin is also a cold working process. All hot working processes must be done above local environment temperature. It is a process of working above room temperature. It is a process of working above recrystallisation temperature of the materials. d Remind it :- above recrystallisation temperature – hot working
Below recrystallisation temperature – cold working
Hot working or Hot forming: Plastic deformation of metal carried out at a temperature above the recrystallization temperature is called hot working.
Under the action of heat and force, when the atoms of metal reach a certain higher energy level, the new crystals start forming.
This is called recrystallization. In hot working, the temperature at which the working is completed is critical since any extra heat left in the material after working will promote grain growth, leading to poor mechanical properties of a material.
In comparison with cold working, the advantages of hot working are No strain hardening Lesser forces are required for deformation Greater ductility of material is available, and therefore more deformation is possible Favourable grain size is obtained leading to better mechanical properties of a material Equipment of lesser power is needed No residual stresses in the material
Cold Working: Plastic deformation of metals below the recrystallization temperature is known as cold working.
It is generally performed at room temperature.
In some cases, slightly elevated temperatures may be used to provide increased ductility and reduced strength		 Comments Active
10 For a laminar flow through a circular pipe, the wall shear stress across a section is a function of _______________. The pressure gradient and the radius R \(\frac{dp}{dz} \) Only the pressure gradient \(\frac{dp}{dz}\) The pressure gradient and the axial velocity \(\frac{dp}{dz}\) \(V_{z}\) The pressure gradient and the radial coordinate r \(\frac{dp}{dz}\) a Shear stress is proportional to the radial distance from the centre of the pipe. Therefore, for laminar flow through a round pipe, the shear stress varies linearly with the radial distance. Comments Active
11 Which fluid is used to increase the rate of evaporation of the liquid ammonia passing through the evaporator in domestic Electrolux refrigeration system? Mercury Hydrogen Water Ammonia b The “hydrogen” being the lightest gas, is used to increase the rate of evaporation (the lighter the gas, faster is the evaporation) of the liquid ammonia passing through the evaporator. Comments Active
12 Which of the following is NOT an example of brittle material? Cast iron High carbon steel Aluminium Ceramic materials c • Materials, such as metals and ceramics, are classified as either brittle or ductile based on their response to stress. Being brittle or ductile is related to a material's ability to deform plastically (without breaking) when subjected to stress.
• Brittle materials, when subjected to stress, exhibit little to no deformation before failure. Rather, they tend to fracture abruptly under the application of a force. Prime examples of brittle materials include high-carbon steel, ceramics, and cast iron.
• High-carbon steel, which contains a higher percentage of carbon compared to other types of steel, tends to be quite strong and hard. However, because of this high carbon content, it becomes more brittle, making it more prone to fracturing under stress without significant deformation.
• Ceramic materials, too, are typically brittle. Despite being incredibly hard and able to resist high temperatures and chemical erosion, ceramics lack ductility. Hence, they can break or shatter suddenly when a certain stress threshold is surpassed.
• Cast iron is another example of a brittle material. Though it offers excellent compressive strength, cast iron's tensile strength is not as remarkable. This means, while it can handle forces that try to squeeze or compress it, it's prone to cracking under forces that attempt to stretch or pull it apart.
• Aluminium, however, does not fit the criteria of a brittle material. It is, in fact, an example of a ductile material, known for its ability to deform under tensile stress without breaking or fracturing. This metal can be pulled into thin wires or hammered into thin sheets. Its significant plastic deformation ability before rupture makes it a material of choice for manyapplications that demand durability and malleability, from soda cans to aeroplane parts. Thus, aluminium is not considered a brittle material.		 Comments Active
13 If the pressure intensity at a point in a fluid is given as 2.7 N/cm2, then what will be the pressure head of oil of specific gravity 0.9 at that point? Take g = 10 m/s2. 3 cm of oil 30 cm of oil 3 mm of oil 3 m of oil d Given
\(P=2.7 NM/cm^{2}\)
\(h=?\)
\(ρ=900 kg/m^{3}\)
\(g=10 m/s^{2}\)
\(P=ρgh\)
\(2.7×10^{4}=900×10×h\)
\(h=\frac{2.7×10000}{9000}\)
\(h=\frac{27}{9}=3\)
\(h=3m\)		 Comments Active
14 In the Bell-Coleman refrigeration cycle, the temperature of the refrigerant is maximum at the: End of isentropic expansion End of isentropic compression Start of isentropic compression End of constant pressure cooling process b The maximum temperature in the cycle is attained at the end of the isentropic compression process. Isentropic or adiabatic compression is the process where the refrigerant is compressed without any heat exchange with the surroundings. Due to the compression work done on the refrigerant, its pressure and temperature increase, reaching a maximum at the end of this compression process. Comments Active
15 Which of the following is NOT a merit of dead weight safety valve? It is a good choice for low-pressure vessels Suitable for high pressure boiler Simplicity of design Gives satisfactory performance during operation b Large amount of weights will be required to balance high pressure; therefore, it is not suitable for high pressure boilers. It is used in low pressure and low capacity boilers Comments Active
16 In case of dual cycle of an IC engine, heat addition is __________. Both an isochoric and an isobaric process  Anisentropic process Only an isobaric process Only an isochoric process a Dual combustiOn cycle has the following processes as shown in the diagram:

Process 1 – 2: Isentropic compression
Process 2 – 3: Cosnstant volume (isochoric) heat additon
Process 3 – 4: Constant pressure (isobaric) heat additon
Process 4 – 5: Isentropic expansion process
Process 5 – 1: Constant volume heat rejection		 Comments Active
17 Water is flowing steadily at a velocity of 20 m/s through a pipe of diameter 0.2 m. The pressure and elevation at point X are 400 kN/m² and 32 m, respectively, while those at another point Y are 300 kN/m² and 34 m, respectively. What will be the head loss between the points X and Y?
Take g = 10 m/s².		 6 m 8 m 10 m 4 m b Given
\(v=20 m/s\)
\(D=0.2 m\)
; \(P_{1}=400 KN/m^{2}\) \(P_{2}=300 KN/m^{2}\)
\(Z_{1}=32m\) \(Z_{2}=34 m\)
According to Bernoullis Theorem
\(\frac{P_{1}}{ρg}+\frac{v^{2}}{2g}+Z_{1}=\frac{P_{2}}{ρg}+\frac{v^{2}}{2g}+z_{2}+hf\)
\(\frac{400×10^{3}}{1000×10}+32=\frac{300×10^{3}}{1000×10}+34+h_{f}\)
\(\frac{100×1000}{1000×10}+32-34=h_{f}\)
\(h_{f}=10-2\)
\(h_{f}=8m\)		 Comments Active
18 The reversible adiabatic process in Mollier chart is represented by _________. A line parallel to the saturated water line A vertical line A horizontal line A line parallel to the saturated vapour line b Vertical lines represents reversible adiabatic process while horizontal lines represent isenthalpic process.
 Comments Active
19 0.2 m3 of an ideal gas at the pressure of 2 MPa and 600 K is expanded isothermally to 5 times the initial volume. It is then cooled to 300 K at constant volume and then, compressed back polytropically to its initial state. The pressure just after the constant volume process is _______. 0.4 MPa 0.8 Mpa 0.2 MPa 2.0 Mpa c Considering process 1 – 2 is isothermal,
\(i.e., T_{1}=T+2=600K\)
\(P_{2}=\frac{P_{1}V_{1}}{V_{2}}=\frac{2×10^{6}×0.2}{(5×0.2)}=400×10^{3} N/m^{2}\)
Work done
\(W_{1-2}=P_{1}V_{1} log_{e}\frac{V_{2}}{V_{1}}=2×10^{6}×0.2 log_{e} 5\)
\(=643775 J\)
Considering process 2 – 3 which is at constant volume
i.e. \(V_{2}=V_{3}=5×0.2=1m^{3}\)
\(P_{3}=P_{2}×\frac{T_{3}}{T_{2}}=400×10^{3}×\frac{300}{600}\)
\(=200×10^{3} N/m^{2}=0.2MPa\)		 Comments Active
20 Which of the following is an isochoric process? Heating of steam in a closed rigid vessel. Heating of steam in a cylinder containing a sliding piston. Heat is supplied during evaporation. Heat supplied is zero. a A rigid vessel means the volume cannot change, so this is an isochoric process. Constant volume process is known as isochoric process. Comments Active
21 The value of the gross stage efficiency and Blade efficiency of the single stage of the impulse turbine are 65% and 78% respectively then the value of the nozzle efficiency will be 83.33 % 50.7 % 50 % 100% a Given
\(η_{G}=0.65\)
\(η_{B}=0.78\)
\(η_{Gross}=η_{blade}×η_{nozzle}\)
\(η_{nozzle}=\frac{η_{Gross}}{η_{blade}}=\frac{0.65}{0.78}\)
\(η_{nozzle}=0.833\)
\(=83.33%\)		 Comments Active
22 The evaporation of feedwater at 100°C into dry and saturated steam at 100°C at atmospheric pressure is known as Boiler horsepower Boiler efficiency Equivalent evaporation Actual evaporation c Equivalent evaporation: It is defined as the amount of dry and saturated steam generated from feed water at 100°C at normal atmospheric pressure. Comments Active
23 The amount of water striking the runner of the reaction turbine is controlled by _____. Casing Spear arrangement Guide mechanism Draft tube c  function of guide mechanism:
Water is brought to the hydroelectric plant site through large penstocks at the end of which there will be a nozzle, which convert the pressure energy completely into kinetic energy. This will convert the liquid flow into a high-speed jet, which strikes the buckets or vanes mounted on the runner, which in-turn rotates the runner of the turbine.
The amount of water striking the vanes is controlled by the runner of the turbine.
The amount of water striking the vanes is controlled by the forward and backward motion of the spear. As the water is flowing in the annular area between the nozzle opening and the spear, the flow gets reduced as the spear moves forward and vice-versa.		 Comments Active
24 In the given T-S diagram of Otto cycle, which of the following processes is a heat addition process?
 2-3 4-1 1-2 3-4 a The schematic of each process of Otto cycle are-

1. Process 1 - 2: Isentropic compression
2. Process 2 - 3: Constant volume or isochoric heat addition
3. Process 3 - 4: Isentropic expansion
4. Process 4 - 1: Constant volume or isochoric heat rejection		 Comments Active
25 What is the unit of measurement of actual evaporation in steam boilers? Kg kg fuel burnt / kg water evaporated m3/kg kg water evaporated / kg fuel burnt d \( Actual evaporation=\frac{steam genrated}{Fuel burnt}\)
So , option d will be correct answer.		 Comments Active
26 Heat addition during the constant pressure process is equal to ________. Change in enthalpy Change in entropy Specific heat Change in internal energy a In a reversible constant pressure process, the heat input is the change in enthalpy. So, heat added at constant pressure is equal to change in Enthalpy and it not only increases the temperature (i.e. internal energy) but also does the work. Comments Active
27 If the cutter and workpiece movements are in opposite directions, the milling process is known as – Face milling Up milling Down milling Side milling b Conventional (Up) Milling. Here,the direction of feed of the worktable isopposite to the direction of rotation of the cutter.
Climb (Down) Milling. Here, the direction of the worktable feed and the rotation of the cutter is the same.

 Comments Active
28 In two-stroke petrol engine, the air Fuel mixture is prepared Inside the Transfer Port Inside the carburetor but outside the cylinder Inside the carburetor and Inside the cylinder Inside the Crank case chamber b Two – stroke spark ignition or petrol engine:
In a two stroke petrol engine, the air – fuel mixture is prepared inside the carburetor but outside the cylinder.
This is in contrast to four – stroke engines, where the air – fuel mixture is prepared in the intake manifold and then drawn into the cylinder during the intake stroke.
The carburetor in a two – stroke engine is responsible for mixing the gasoline with air in the correct proportion.
The air in drawn into the carburetor through an air filter, and the gasoline is metered through a fuel jet.
The mixed air – fuel mixture is then sprayed into the crankcase, which is the space below the piston in the engine.		 Comments Active
29 The velocity of flow between two adjacent streamlines is inversely proportional to the: Spacing of the streamlines Specific weight Volume flow rate Circulation a Streamlines are the lines drawn through the flow field in such a manner that the velocity vector of the fluid at every point on the streamline is tangent to the streamline at that instant. Using the continuity equation it can be shown that the speed of flow is inversely proportional to the spacing between streamlines. Comments Active
30 The point of intersection of the line of action of the resultant hydrostatic force and the submerged surface is called _____. Centre of buoyancy  Centre of pressure Centre of gravity Centre of mass b The point of intersection of the line of action of the resultant hydrostatic force and the corresponding surface is called the center of pressure. The Centre of pressure is also defined as the point of application of the total pressure on the corresponding surface. Comments Active
31 According to _________, the intensity of pressure in a liquid at rest is constant in all directions. Hydrostatic law Newton’s law Pascal’s law Boyle’s law c Pascal's law: According to Pascal's Law, the pressure or intensity of pressure at a point in a static fluid is equal in all directions. Comments Active
32 What is the main function of the condenser in a Rankine cycle power plant? To decrease the efficiency of the cycle To condense the steam till it transforms into saturated liquid To increase the pressure of the steam To increase the temperature of the cooling water b A large heat exchanger designed to cool exhaust steam from a turbine below the boiling point so that it can be returned to the heat source as water. Comments Active
33 If difference of axial components of velocity at inlet and outlet of a de-Laval turbine is found to be 120 m/s and mass flow rate of steam is 7 kg/s then axial thrust on the rotor is 7 N 840 N 17.14 N 120 N b Given
\(V=V_{out}-V_{in}=120m/s\)
\(m=7Kg/s\)
(Axial thrust) \(F=m×(V_{out}-V_{in})\)
\(F=7×120\)
(Axial thrust) \(F=840N\)		 Comments Active
34 Which of the following evaporators are also known as prime-surface evaporators? Finned-tube evaporators Bare-tube coil evaporators Shell-and-tube evaporators Plate evaporators b Bare tube evaporator: This type of evaporator is also called prime-surface evaporator. The bare tube coil evaporators are extensively used in household refrigerators because they are easier to keep clean. The material used for bare tube evaporator is steel or copper. Comments Active
35 On the stress-strain diagram, the material obeys Hooke’s law till: Point of ultimate stress Lower yield point Elastic limit Upper yield point c Hooke's Law states that when a material is loaded within elastic limit, the stress is proportional to the strain produced by the stress. This means the ratio of the stress to the corresponding strain is a constant within the elastic limit. This constant is known as Modulus of Elasticity or Modulus of Rigidity or Elastic Modulii.

(Reference : Strength of Material by R.K Bansal –page no.-6)		 Comments Active
36 The process of pushing the heated billet or slug of metal through an die orifice, thus forming an elongated part of a uniform cross-section corresponding to the shape of the die orifice is known as ____________ Drawing process Rolling process  Machining process Extrusion process d
In the extrusion process, a heated billet or slug of metal is forced through a die orifice, thus forming an elongated part of a uniform cross-section corresponding to the shape of the die orifice.
The rolling process, on the other hand, involves passing a billet or slab of metal between two rollers to reduce its thickness and increase its length.
The drawing process involves pulling a billet or bar of metal through a die to reduce its diameter and increase its length.
The drawing process involves pulling a billet or bar of metal through a die to reduce its diameter and increase its length.
The machining process involves removing material from a workpiece to create the desired shape and dimensions.
Squeezing toothpaste from a tube is a familiar example of extrusion. In extrusion billet experiences compressive stress. Various factors on which an extrusion process depends are die design, extrusion ratio, billet temperature, lubrication, extrusion speed, and metal properties. Among these, the most important factor is metal property. For successful extrusion to happen the metal should be plastic.		 Comments Active
37 In the context of work done of turbine, the power developed by the runner depends on which of the following parameters? Whirl velocity only Whirl and blade velocities Blade velocity Velocity at the exit of draft tube B

∴The power developed by a turbine runner is directly related to the energy extracted from the working fluid (usually water). This energy extraction occurs through the interaction of the runner blades with the fluid flow. Two key parameters influence this interaction and, consequently, the power developed:
Whirl Velocity (Vw): This is the tangential velocity of the fluid particles relative to the runner axis. It represents the potential energy of the fluid due to its rotation.
Blade Velocity (U): This is the tangential velocity of the runner blades. It represents the kinetic energy of the blades and their ability to extract energy from the fluid.		 Comments Active
38 In the boiler mountings, the blow-off cock is fitted at ______. The top of the boiler shell  The bottom of the boiler shell The middle of the boiler shell Near the steam supply line b The blow-off cock helps to drain out the water periodically from the boiler. It is mounted at the lowest portion of the boiler Comments Active
39 Which one of the following is correct statement about Blade cross sectional fluid flow area from inlet to outlet of a turbine? Constant for reaction turbine and diverging for impulse turbine Constant for impulse turbine and converging for reaction turbine Constant for reaction turbine and converging for impulse turbine Constant for impulse turbine and diverging for reaction turbine B In an impulse turbine, the cross-sectional fluid flow area remains constant from the inlet to the outlet.
Impulse turbines allow the steam to expand and drop in pressure before it enters the turbine in a high-speed jet, hitting the turbine blades and causing them to turn.
The energy extraction in this design type is based solely on the impulses of changing momentum caused by the redirected flow.
On the other hand, in a reaction turbine, the fluid's pressure energy is gradually converted into kinetic energy as it passes through the rotor blades. As the fluid accelerates, the flow area narrows to maintain a constant mass flow rate. Therefore, the cross-sectional area converges from the inlet to the outlet.
Hence, these distinct mechanisms of operation lead to different designs in terms of the cross-sectional fluid flow area from inlet to outlet in impulse and reaction turbines.		 Comments Active
40 Which of the following equations is NOT used in deriving the expression for discharge through the steam nozzle? Momentum equation Newton’s equation of viscosity Continuity equation Steady flow energy equation b Equations is used in deriving the expression for discharge through the steam nozzle are
Momentum equation, Continuity equation, Steady flow energy equation.
\(m_{max}=An(\frac{p_{1}}{v_{1}})(\frac{2}{n+1})^{\frac{n+1}{n-1}}\)		 Comments Active
41 The bent tube of a Bourdon tube pressure gauge will change its shape when exposed to variations of _______. Displacement Resistance Voltage Pressure d The Bourdon tube works on a simple principle that a bent tube will change its shape when exposed to variations of internal and external pressure. As pressure is applied internally, the tube straightens and returns to its original form when the pressure is released. Comments Active
42 The pressure intensity at a point in a fluid is given as 3.924 N/cm2. What will be the corresponding height of fluid when the fluid is water? 3.5 m of water  2.5 m of water 6 m of water 4 m of water d Given
\(P=3.924 N/cm^{2}=3.924×10^{4} N/m^{2}\)
\(h=?\)
\(ρ=1000 kg/m^{3}\)
\(g=9.81 m/s^{2}\)
\(P=ρgh\)
\(\frac{3.924×10^{4}}{1000×9.81}=h\)
\(h=4m\)		 Comments Active
43 If head imparted by impeller to water is equal to manometric head, then the manometric efficiency of the centrifugal pump will be: 75%  50% 0% 100% d \( η_{manometric}=\frac{manometric head}{head imparted by impeller to water}\)
Now, if the head imparted by the impeller to the water is equal to the manometric head (that is, Hm = Hi ), then the manometric efficiency is 1 or 100% when expressed in percentage form. So, in this scenario, all the energy given to the impeller is effectively converted into pressure energy at the pump discharge, leading to maximum manometric efficiency.		 Comments Active
44 Which of the following is NOT the part of venturimeter setup? Converging part Float Throat Diverging part b Comments Active
45 Ammonia is NOT used in domestic refrigeration and comfort air-conditioning because: It is toxic and flammable It is not soluble in water Lubricating oil is not soluble in ammonia at all Its heat transfer coefficient is very low a Ammonia is not used in comfort air conditioning and in domestic refrigeration because of inflammatory and toxicity.
 Comments Active
46 If the temperature of 'A' is equal to the temperature of 'B' and 'C', then the temperature of 'B' will be equal to the temperature of 'C'. This is known as: Joule's law Law of thermal equilibrium Law of equality of temperature  zeroth law of thermodynamics d When a body, ‘A’, is in thermal equilibrium with another body, ‘b’, and also separately in thermal equilibrium with a body ‘, C’, then body, ‘B’ and ‘C’, will also be in thermal equilibrium with each other. This statement defines the zeroth law of thermodynamics. The law is based on temperature measurement. Comments Active
47 The difference in low temperature cascade condenser temperature and high temperature cascade evaporator temperature is called ___________.  Temperature overlap Degree of subcooling Average temperature Degree of superheat a Temperature overlap is the difference in temperature between the condenser of the low-temperature (LT) cycle and the evaporator of the high-temperature (HT) cycle in a cascade refrigeration system. It is a crucial parameter in determining the system's efficiency and performance. Comments Active
48 Latent heat of vaporisation is NOT the _______. Heat required for complete conversion of ice into water Heat added at constant temperature of 100°C to convert water into steam Sum of internal latent heat and external work of evaporation Heat required for complete conversion of saturated liquid into dry saturated vapour a When a material in liquid state is given energy, it changes its phase from liquid to vapour without change in temperature, the energy absorbed in the process is called latent heat of vaporization. Comments Active
49 The SI unit of specific heat is Jkg/K JK/kg  J/kg.K  J/kg c The SI unit of specific heat is J/kg.K
 Comments Active
50 Which of the following statements is correct about the forced-draught fan used in steam boilers? The power required by an induced-draught fan is equal to that required by a forced-draught fan for the same amount of draught. The power required by an induced-draught fan is greater than that required by a forced-draught fan for the same amount of draught. The power required by an induced-draught fan is less than that required by a forced-draught fan for the same amount of draught. The power required by an induced-draught fan may be greater than or less than that required by a forced-draught fan for the same amount of draught. b Difference between Forced Draft and Induced Draft
Forced Draft Fans require less power whereas, Induced Draft Fans require more.
The pressure within flue gases is somewhat more than atmospheric pressure in FD Fans while, in ID Fans, the pressure within flue gases is a bit less.
The flow of flue gases is more uniform in the Forced Draft Fans and less uniform in Induced Draft Fans.
Lastly, the risk of fire in case of any kind of leakages is high with Forced Draft Fans whereas, there is no danger of fire through leakages in Induced Draft Fans.		 Comments Active
51 The unit of density in FPS (Foot Pound System) is given by: \(Ib/ft^{1}\) \( Ib/ft^{2}\) \( Lb^{2}/ft^{3}\) \( Ib/ft^{3}\) d Density is equal to mass per volume, Where volume is L³, or cube of length factor. Putting it in FPS, the mass is measured in pounds or Ibs, and length "L" is measured foots or ft. by combining these we get, Ib/ft³. Comments Active
52 A thermometer works on the principle of ____________. 3rd law of thermodynamics Joule’s law 2nd law of thermodynamics Zeroth law of thermodynamics d When a body, ‘A’, is in thermal equilibrium with another body, ‘b’, and also separately in thermal equilibrium with a body ‘, C’, then body, ‘B’ and ‘C’, will also be in thermal equilibrium with each other. This statement defines the zeroth law of thermodynamics. The law is based on temperature measurement. Comments Active
53 Which of the following statements is correct about water-tube and fire-tube boilers? In case of fire-tube boilers, hot gases flow in the tubes. In case of water-tube boilers, hot gases flow in the tubes. In case of fire-tube boilers, hot gases are surrounded over the tubes. In case of fire-tube boilers, water flows in the tubes. a In a fire tube boilers hot flue gas travels through tubes that are surrounded by water. In case of water-tube boilers the water heats by traveling through a tube surrounded by flue gas.
Remind it: - What is inside that matter always, if water is inside the tube called water tube boiler if fire is inside the tubes called fire tube boiler.		 Comments Active
54 Match the types of refrigerants with their representations.
Types of Refrigerant
Representation
1. CFC refrigerants
a. R – 22
2. HFC refrigerants
b. R – 11
3. HC refrigerants
c. R – 134a
4. HCFC refrigerants
d. R – 290		 1-b; 2-d; 3-c; 4-a 1-a; 2-d; 3-b; 4-c 1-a; 2-c; 3-d; 4-b 1-b; 2-c; 3-d; 4-a d R – 22 also known as chlorodifluoromethane (CHClF2), is a hydrochlorofluorocarbon (HCFC) refrigerant that was once widely used in air conditioning and refrigeration systems.
R – 11, also known as trichlorofluoromethane (CCl3F), is a chlorofluorocarbon (CFC) refrigerant that was once widely used in air conditioning and refrigeration systems.
R – 134a, also known as norflurane or Freon 134a, is a hydrofluorocarbon (HFC) refrigerant commonly used in automobiles, refrigerators, and other cooling applications.
R – 290, also known as propane, is a hydrocarbon refrigerant commonly used in small, stand-alone refrigeration applliances such as freezers, drink machines, and display coolers.		 Comments Active
55 What is the value of density of water on 4áµ’C? 10 gm/cm3 1000 gm/cm3 100 gm/cm3 1 gm/cm3 d Water has its maximum density of 1g/cm3 or 1000 kg/m3 at 4 degrees Celsius. Comments Active
56 Which of the following is NOT a type of steam separator? Reciprocating type Impact or baffle type Reverse current type Centrifugal type a Steam coming from the boiler may be wet, dry, or superheated. However, during piping to the turbine or engine, it may get some wetness.  The use of wet steam in steam engines or turbines is uneconomical as well as it also possesses some risks.
The function of the steam separator is to remove entrained water particles. It is installed close to the steam engine or turbine.
Classification:
Impact of baffle type
Reverse current type
Centrifugal type		 Comments Active
57 Which of the following is the correct item for Double Volute in centrifugal pumps? Flow separation does not take place Flow is separated into two unequal streams by two-cut waters that are 90° apart Flow is separated into two equal streams by two-cut waters that are 90° apart Flow is separated into two equal streams by two-cut waters that are 180° apart d  Double volute casings have two cutwaters located 180 degrees apart from each other. 
 Comments Active
58 A circular opening, 3 m diameter, in a vertical side of a tank is closed by a disc of 3 m diameter which can rotate about a horizontal diameter and depth of centre of gravity from free surface is 4 m. What will be the total pressure on the disc? 175.7 kN 234.89 kN 100 kN 277.4 kN d
Given
\(D=3 m\)
\(h=4m\)
\(ρ=1000 kg/m^{3}\)
\(g=9.81 m/s^{2}\)
\(F=ρgAh\)
\(F=1000×9.81×\frac{π}{4}×3^{2}×4\)
\(F=277371.21 N\)
\(F=277.371 KN\)		 Comments Active
59 Which of the following pressure measurement devices consists of a hollow metal tube bent like a hook whose end is closed and connected to a dial indicator needle? Piezoelectric transducers Strain-gauge pressure transducers Pressure transducers Bourdon tube d The Bourdon gauge consists of a tube bent into a coil or an ar(c) As the pressure in the tube increases, the coil unwinds. A pointer connected to the end of the tube can be attached to a lever and a pointer calibrated to indicate pressure. Comments Active
60 Which of the following is the correct expression for pressure intensity? \(P=1.5ρgh\) \( P=2ρgh\) \( P=0.5ρgh\) \( P=ρgh\) d Hydrostatic law considers the fluid at rest. However, under shear stress, maintaining the rest condition is possible. As such, the fluid exerts pressure on the surface in contact. The fluid attempts to maintain the hydrostatic equilibrium, which means the upward and downward forces acting on the surface exactly balance each other.
At depth z, if the pressure P acts on the surface, the equilibrium condition can be expressed with Newton’s second law of motion as:
\(\frac{dP}{dz}=-ρg\)
This can alternately be written as:
\(P=ρgh \)
Here, h is z-z。.		 Comments Active
61 Which of the following about work transfer is NOT correct? Work transfer is a boundary phenomenon. Work is given by the area under the curve on p-V diagram in case of non-flow process. Work is a transient phenomenon. Work transfer is a thermodynamic property. d Work and heat are not thermodynamic properties, but rather process quantities: flows of energy across a system boundary. Systems do not contain work, but can perform work, and likewise, in formal thermodynamics, systems do not contain heat, but can transfer heat. Comments Active
62 In which of the following cycles does heat addition NOT take place at constant volume? Diesel cycle Otto cycle Dual cycle Lenoir cycle a Diesel cycle is also known as a constant pressure cycle as heat is supplied at constant pressure is in this cycle. A Diesel cycle is shown below

Process 1 – 2 is isentropic compression
Process 2 – 3 is constant pressure heat addition
Process 3 – 4 is isentropic expansion
Process 4 – 1 is a constant volume heat rejection
Option are correct descriptions of the Diesel cycle.		 Comments Active
63 Which of the following ideal gas processes has the highest polytropic index? Isentropic process Isobaric process Isothermal process Isochoric process d For Isochoric process (v =constant) the value of polytrophic index will be . \(∞\) Comments Active
64 In Bell-Coleman Cycle, the pressure at the end of isentropic compression is same as: the pressure at the start of isentropic expansion the pressure in constant pressure expansion the pressure at the start of isentropic compression the pressure at the end of isentropic expansion a The working fluid of the bell Coleman Refrigeration cycle is Air. This system of refrigeration and it has light weight.
 Comments Active
65 In the refrigeration system, heat rejection factor is the ratio of ___________. load on the condenser to the COP work done by compressor to the refrigeration capacity refrigeration capacity to the work done by compressor heat rejected to the refrigeration capacity d \(HRR=1+\frac{1}{COP}=1+\frac{W_{input}}{RE}=\frac{Q_{COND}}{RE}\)
Or
\(HRR=Heat rejection ratio=\frac{Q_{COND}}{RE}\)
Where,
is heat rejected in the condenser, \(Q_{COND}\)
RE is the Refrigeration effect and Winput is the work input to the Refrigeratio system
Heat rejected in the condenser is always more than heat absorbed in the evaporator.
So, the heat rejection factor in vapour compression refrigeration system will be more than one.		 Comments Active
66 A closed system undergoes a process in which the work done by the system is 100 J and the internal energy decreases by 50 J. According to the first law of thermodynamics, what is the amount of heat transferred into or out of the system? 50 J 150 J – 150 J – 50 J a Given
\(dW=100 J\)
\(dU- -50J\)
According to firs law of thermodynamics
\(dQ=dU+dW\)
\(=-50+100\)
\(dQ=50J\)		 Comments Active
67 In a Carnot cycle, _______. all processes are reversible only isothermal processes are reversible all processes are irreversible only adiabatic processes are reversible a A reversible cycle is an ideal hypothetical cycle inwhich all the processes constituting the cycle are reversible. Carnot cycle is a reversible cycle.
The Carnot cycle consists of 4 processes
1 – 2 isothermal heat addition
2 – 3 reversible adiabatic expansion
3 – 4 isothermal heat rejection
4 – 1 reversible adiabatic compression
(Reference :- basic thermodynamics by p.k nag – page no.-91)		 Comments Active
68 Functionality of nozzle is that,________ It produces steam at very low velocity It produces steam at very low pressure It produces steam jet at very high pressure It produces steam jet at very high velocity d A nozzle is a device designed to control the direction or characteristics of a fluid flow (specially to increase velocity) as it exits (or enters) an enclosed chamber or pipe. Comments Active
69 In actual air-conditioning applications for R-12 and R-22 refrigerant and operating at a condenser temperature of 40°C and an evaporator temperature of 5°C, the heat rejection factor is about: 1 1.25 2.15 5.12 b \(T1=5℃ or 273+5=278K\)
\(T2=40℃ or 273+40=313K\)
\(C.O.P=\frac{T1}{T2-T1}\)
\(=\frac{278}{313-278}\)
\(=\frac{278}{35}\)
C.O.P. = 7.942
Heat rejection factor (HRF)
\(=1+\frac{1}{C.O.P.}\)
\(=1+\frac{1}{7.942}\)
\(=\frac{8.942}{7.942}\)
\(=1.12\)		 Comments Active
70 If the line of stroke of a follower passes through the centre of rotation of a cam, then the cam is called _________. radial cam offset cam oscillating cam and follower globoidal cam a Radial or Disc Cams: A cam in which th efollower moves radially from the centre of rotation of the cam is known as radial or disc cam.
Radial Follower: The follower is k n own as a radial follower if the line of movemnet of the follower passes through the centre of rotation of the cam.		 Comments Active
71 The figure shows the P – V diagram of the ______.
 Otto cycle Open cycle gas turbine Steam turbine Steam engine b Brayton cycle consist of 4 processes-
Isentropic compression (in a compressor)
Constant – pressure heat addition
Isentropic expansion (in a turbine)
Constant – pressure heat rejection		 Comments Active
72 A Kaplan turbine has an outside diameter of runner and hub diameter as 4 m and 2 m, respectively. If the velocity of flow at inlet is 8 m/s, then what will be the discharge passing through the turbine? 6.8 m3/s 75.36 m3/s 68 m3/s 7.536 m3/s b Given:
Tip Diameter, \(D_{0}=4m, D_{h}=Hub Diameter,=2m, V_{f}_{1}=Flow velocity=8 m/s\)
Discharge, \(Q=\frac{Ï€}{4}(D02-Dh2)V_{f}_{1}\)
\(Q=\frac{π}{4}(4^{2}-2^{2})×8=75.36 m^{3}/s\)		 Comments Active
73 In which percentage generally is lubricating oil mixed with the fuel, which is then inducted into the carburettor in a mist lubricating system? 3% to 6% 40% to 50% 0 30% to 40% a Mist lubrication system:
In two – stroke engines, mist lubrication is used where crankcase lubrication is not suitable. In a two – stroke engine, as the charge is compressed in the crankcase, it is not possible to have the lubricating oil in the sump. Hence, mist lubrication is adopted in practice.
In such engines, the lubricating oil is mixed with the fuel, the usual ratio being 3% to 6%. The oil and fuel mixture is inducted through the carburetor.
The fuel is vaporized and the oil (mist form) goes through the crankcase into the engine cylinder. The mist from the oil strikes the crankcase walls, lubricates connecting rod bearings, and the remaining oil lubricates the piston, piston rings, and the cylinder.		 Comments Active
74 If the C.O.P. of 1 TR ammonia-water absorption refrigeration plant is 0.5, then the heat supplied in the generator is ___________. (1 TR = 3.51 kw) 1.5 kW 7 kW 3.5 kW 10.5 kW b Given
1 Ton = 3.5 KW
\(Q_{2}=3.5 kW\)
COP = \(\frac{Q_{2}}{W_{supplied}}\)
\(0.5=\frac{3.5}{W_{Supplied}}\)
\(W=7KW\)		 Comments Active
75 Scavenging phenomenon occurred in Two-stroke IC engine when Both transfer port and exhaust port are fully closed Both inlet and outlet Valve are opened for a while simultaneously Both inlet and outlet Valve are fully closed Both transfer Port and exhaust port are opened for a while simultaneously d The process of simultaneously purging exhaust gas and filling the cylinder with fresh charge for a new cycle is referred to as scavenging. The main scavenging methods are cross scavenging, loop scavenging and uniflow scavenging.
Since one engine cycle in a two-stroke engine is completed in one crankshaft rotation, gas exchange has to occur while the piston is near BDC. There are two important consequences of this:
Since gas exchange commences before and ends after BDC, a portion of the expansion and compression stroke is unusable.
Piston velocity is low during the entire gas exchange phase and is unable to provide a significant pumping effect on the cylinder charge. Hence, gas exchange can only occur when the intake pressure is sufficiently higher than the exhaust pressure to allow the incoming fresh charge to displace the burned gas in the time available. This process of simultaneously purging exhaust gas from the previous cycle and filling the cylinder with fresh charge for a new cycle is referred to as scavenging. To ensure adequate scavenging, two-stroke engines must be equipped with some form of intake air compression and the intake and exhaust ports and/or valves must be open simultaneously for a sufficient period of time.		 Comments Active
76 What pressure head of kerosene of specific gravity 0.8 will be equivalent to a pressure head of 100 m of water? 120 m 125 m 100 m 110 m b Given
\(S_{1}=0.8\)
\(h_{1}=?\)
\(S_{2}=1\)
\(h_{2}=100 m\)
Apply below Relation
\(S_{1}h_{1}=S_{2}h_{2}\)
\(0.8×h_{1}=1×100\)
\(h_{1}=\frac{100}{0.8}\)
\(h_{1}=125m\)		 Comments Active
77 A cantilever beam carries a uniformly distributed load over a span of 1 m as shown in the figure below. The reactive moment at point A is _________.
 30 kN - m 10 kN - m 5 kN - m 0 kN - m c Comments Active
78 The continuity equation n is valid for a ______. \(\frac{∂u}{∂x}+\frac{∂v}{∂y}=0\) Unsteady, 2D, incompressible flow Unsteady, 2D, compressible flow Steady, 2D, compressible flow Steady, 2D, incompressible flow d The general form of the continuity equation in Cartesian coordinates:
\(\frac{∂_{ρ}}{∂_{t}}+\frac{∂}{∂_{x}}(ρu)+\frac{∂}{∂_{y}}(ρv)+\frac{∂}{∂_{z}(ρw)}=0\)
For steady flow:
\(\frac{∂_{ρ}}{∂_{t}}=0\)
\(\frac{∂}{∂_{x}}(ρu)+\frac{∂}{∂_{y}}(ρv)+\frac{∂}{∂_{z}}(ρ_{w})=0\)
If the fluid is incompressible, then 𝛒 is constant so variation of a 𝛒 with respect to any variable (time or space variables) will be zero.
\(\frac{∂_{ρ}}{∂_{t}}=0\)
Also,
\(\frac{∂_{u}}{∂_{z}}+\frac{∂_{v}}{∂_{y}}+\frac{∂_{w}}{∂_{z}}=0\)
The continuity equation is valid for a Steady, 2D, incompressible flow. \(\frac{∂u}{∂x}+\frac{∂v}{∂y}=0\)		 Comments Active
79 A solid circular shaft of diameter d is subjected to the twisting moment T. Which of the following relations can be used to determine the stress developed in the shaft? \(Ï„=\frac{128T}{Ï€d^{3}}\) \( Ï„=\frac{64T}{Ï€d^{3}}\) \( Ï„=\frac{32T}{Ï€d^{3}}\) \( Ï„=\frac{16T}{Ï€d^{3}}\) d \( \frac{T}{J}=\frac{Ï„}{r}\)
\(Ï„=\frac{T2d}{\frac{Ï€d^{4}}{32}}=\frac{16T}{Ï€d^{3}}\)		 Comments Active
80 Which of the following statements related to rope drives is INCORRECT? It is used to transmit power only for shorter distances. Rope drives have high mechanical efficiency. It has good crushing resistance. Shafts do not require exact alignment. a The advantages of using rope drive are
• The tension in it is uniformly distribute(d)
• Net driving tension is more than that of belt drive
• Frictional grip is more than belt drives.
• Using one rope for each groove poses difficulty in tightening the ropes to the same extent but with the advantage that the system can continue its operation even if a rope fails.
• The repair can be undertaken when it is convenient.
• Preferred for long center distances between the shafts,
• Ropes being cheaper as compared to belts		 Comments Active
81 What will be the ratio of the pressure intensities of two fluids, one with a liquid column of 0.4 m of water and the other with a liquid column of 0.2 m of an oil of specific gravity 0.8? 2 \(\frac{7}{2}\) \(\frac{3}{2}\) \(\frac{5}{2}\) d Given
\(h_{w}=0.4m\)
\(ρ_{w}=1000 kg/m^{3}\)
\(g=981 m/s^{2}\)
\(h_{o}=0.2m\)
\(ρ_{o}=800 kg/m^{3}\)
\(\frac{ρ_{w}}{ρ_{o}}=\frac{1000×0.4×9.81}{800×0.2×9.81}\)
\(\frac{ρ_{w}}{ρ_{o}}=\frac{2000}{800}=\frac{5}{2}\)		 Comments Active
82 The correct expression for the dimensional formula of volumetric discharge in the fluid equations is given by _____________. \(L^{3}T^{-2}\) \( L^{3}T^{-3}\) \( L^{2}T^{-1}\) \( L^{3}T^{-1}\) d \(Discharge=Cross-section area of pipe ×velocity\)
\(The unit of volumetric discharge is m^{3}/sec\)
\(Hence, the dimesion of Q=L^{3}T^{-1}\)		 Comments Active
83 Which of the following statements is correct regarding governor? It is not a compulsory device of the prime mover. It controls the mean speed of the prime mover. It controls the temperature of the prime mover. It controls acceleration of the prime mover. b The function of a governor is to maintain the speed of an engine within specified limits whenever there is variation in loa(d) When the speed of engine varies in each revolution, (cyclic variation), it is due to variation in output torque of engine. It can be regulated by mounting a suitable flywheel on the shaft. Comments Active
84 Which of the following statements is INCORRECT about the Benson boiler? The Benson boiler is heavier than other boilers. The average operating pressure for the Benson boiler is higher than 200 bar. Benson boilers can be switched on very quickly. In Benson boilers, drums are not used. a Benson Boiler is a high-pressure, drumless (i.e. There is no recirculation of water​), supercritical, water tube steam boiler with forced circulation. Benson boilers can be switched on very quickly.it have lesser weight compare to other boiler.
 Comments Active
85 An impulse turbine is running at 1000 rpm with a net head 600 m. If the discharge through the nozzle is 0.1 m3/s, then what will be the power available at the nozzle? Take g = 10 m/s2. 450 kW 525 kW 700 kW 600 kW d

Given
\(Q=0.1 m^{3}/s\)
H = 600 m
G = 10m/s2
\(P=\frac{ρQgH}{1000}=\frac{1000×9.81×0.2×500}{1000}=981 KW\)		 Comments Active
86 The dimension formula for specific gravity is given by: \(M^{0}L^{1}T^{1}\) \(M^{1}L^{0}T^{1}\) \(M^{1}L^{1}T^{0}\) \(M^{0}L^{0}T^{0}\) d unit of gravity is or and specific gavity means gravity of fluid with respect to standard fluid that is water .So ratio of gavities will become dimensionless. \(\frac{kg}{m^{2}s^{2}}\) \(\frac{N}{m^{3}}\)
dimension formula : [M0L0T0].
Remind it :- Relative gravity is also the ratio of gavities but not w.r.t water .		 Comments Active
87 For the same temperature limit, which of the following cycles has maximum efficiency? Diesel cycle Otto cycle Normal Stirling cycle Carnot cycle d \(η=1-\frac{Heat Rejected}{Heat Supplied}\)
Since all the cycles reject their heat at the same specific volume, process line from state 4 to 1, the quantity of heat rejected from each cycle is represented by the appropriate area under the line 4 to 1 on the T – s diagram.
As is evident from the equation
The cycle which has the least heat rejected will have the highest efficiency.
Thus, the Otto cycle is the most efficient and the Diesel cycle is the least efficient of the three cycles.
\(η_{otto}>η_{dual}>η_{diesel}\)
For the same compression ratio and the same heat input
\(η_{otto}>η_{dual}>η_{diesel}\)
For constant maximum pressure and heat supplied
\(η_{diesel}>η_{dual}>η_{otto}\)		 Comments Active
88 Which of the following is a forced circulation type of boiler? LaMont boiler Lancashire boiler Cochran boiler Babcock & Wilcox boiler a A LaMont boiler is a type of forced circulation water-tube boiler in which the boiler water is circulated through an external pump through long closely spaced tubes of small diameter. The mechanical pump is employed in order to have an adequate and positive circulation in steam and hot water boilers.
Ex: Lamont , loeffler , velox, bension all are force circulation Boiler.		 Comments Active
89 A workpiece is taper turned using lathe, where large diameter of workpiece is D and small diameter d. If the length of this workpiece is L, then half angle α is given by: \(tanα=\frac{(D-d)}{4L}\) \(tanα=\frac{(D-d)}{2L}\) \(tanα=\frac{(D-d)}{L}\) \(tanα=\frac{(D-d)}{3L}\) b When the diameter of the bar either increases or decreases along the length of the bar then it is called a taper.
This operation is performed on a lathe machine with the help of a taper-turning attachment.
The formula for taper angle is \(α\)

tan = \( α\) \(\frac{D-d}{2L}\)
where, = taper angle, D = large diameter of the bar, d = small diameter of the bar, L = length of the bar. \(α\)		 Comments Active
90 The direction of the friction force is: in the direction of motion of the body in the opposite direction of motion of the body or in the opposite direction of the tendency to move in the inclined direction of the motion of the body in the perpendicular direction of the motion of the body b Friction:When a solid body slides over a stationary solid body, a force is exerted at the surface of contact by the stationary body on the moving body. This force is called the force of friction.
Laws of Dry Friction:
The friction that exists between two surfaces which are not lubricated is known as dry friction.
The following are the laws:
• The limiting frictional force is independent of the shape and area of the surface in contact.
• The force of friction acts in the opposite direction in which the surface is having a tendency to move.
• The frictional force acts tangentially opposite to the direction of motion to the contacting surfaces.
• The force of friction is equal to the force applied to the surface, so long the surface is at rest.
• When the surface is on the point of motion, the force of friction is maximum and this maximum frictional force is called the limiting friction force.
• The limiting frictional force bears a constant ratio to the normal reaction between two surfaces.		 Comments Active
91 Which among the following options has same thermal efficiency under ideal conditions (Operate within the same temperature)? Carnot cycle and Brayton cycle Carnot cycle and Stirling cycle Carnot and dual cycle Carnot cycle and Otto cycle B -
A Carnot cycle consists of four processes: 1. Reversible isothermal heat addition 2. Isentropic (reversible adiabatic) expansion 3. Reversible isothermal heat rejection 4. Isentropic compression of the gas.

Stirling cycle and Ericsson cycle are the modified forms of Carnot cycle. A stirling cycle consists of two reversible isothermal and two reversible constant volume (isochoric) processes.

Which is the same, as Carnot efficiency.		 Comments Active
92 What will be the atmospheric pressure at a location where the barometric reading is 750 mm Hg and the gravitational acceleration is g = 9.81 m/s2? Assume the density of mercury to be 13,600 kg/m3. 100.06 Pa 10.006 kPa 1000.6 Pa 100.06 kPa d We know that pressure exerted by a standing column of fluid is calculated using this equation.
\(P=ρ_{f}gh\)
Given
\(ρ_{f}=13600 Kg/m^{3}\)
\(g=9.81 m/s^{2}\)
\(h=750 mm=0.75 m\)
\(P_{atm}=13600×9.81×0.75\)
\(P_{atm}=100062 Pa\)
\(P_{atm}=100.062 KPa\)		 Comments Active
93 Which of the following statements about equilibrium is correct? Summation of all the forces acting in one direction must not be zero. Summation of all the forces acting in all the possible directions must be zero. Summation of all the forces acting in all the possible directions must be non-zero. Summation of all the forces acting in one direction must be zero. b If the sum of all forces acting on the body is zero, then it is not necessary that the body will be in equilibrium. For the explanation, let us take an example.Let us assume that two equal and opposite forces having their line of action at a certain distance apart act on a body. Then the body in this case will not have translational motion but have rotation due to torque produced. Hence not in equilibrium. If two equal and opposite force act a point or concurrent, then the torque produced will be zero. The body will not have translational and rotational motion and will be in equilibrium.
 Comments Active
94 If the manometeric efficiency and mechanical efficiency of a centrifugal pump are 70% and 80%, respectively, then the overall efficiency will be: 80% 40% 56% 75% c
overall efficiency=hydraulic efficiency X mechanical efficiency =0.80X0.70=0.56=56%		 Comments Active
95 If 5 litres of a certain oil weighs 30 N, then what will be the specific weight of that oil? 600 N/m3 300 N/m3 6000 N/m3 3000 N/m3 c Given \(V=5L=5×10^{-3}m^{3}\)
\(W=30N\)
Now Specific weight \(ω=\frac{W}{V}\)
\(=\frac{30}{5×10^{-3}}=6000N/m^{3}\)		 Comments Active
96 The function of an air pre heater is _____ To increase the temperature of air before entering the furnace To decrease the temperature of air after entering the furnace To increase the temperature of air after entering the furnace To decrease the temperature of air before entering the furnace a The main function of an air preheater is to extract the excess heat from the flue gases in the boiler. As we know, combustion requires air, fuel, and fire to take place. Air preheaters help significantly in feeding the hot air and increasing the combustion efficiency for the operation in steam boilers. Comments Active
97 Which of the following is the advantage of axial flow pump? High volumetric discharge Low volumetric discharge High head Medium discharge pressure a The main advantage of an axial flow pump is that it has a relatively high discharge (flow rate) at a relatively low head (vertical distance).  Comments Active
98 If the lower temperature fixed by the refrigeration application is high, the C.O.P. of the Carnot refrigerator will be ________. Very less High The same Less b If the lower temperature fixed by the refrigeration application is higher than the upper temperature, then COP will increase. Because COP of refrigerator is directly proportional to lower temperature and inversely proportional to the difference between the two temperature. Comments Active
99 Which of the following types of simple manometers measures the gauge pressure of only incompressible fluids? Single column manometer U – tube manometer Differential U – tube manometer Piezometer d A manometer is a device to measure pressures. A common simple manometer consists of a U-shaped tube of glass filled with some liquid. In its simplest form, this type of manometer consists of an incompressible fluid like water or mercury. Comments Active
100 The ratio of the actual mass flow rate to that due to isentropic expansion in the steam nozzle is known as _________. Mach number Coefficient of discharge Nozzle efficiency Critical pressure ratio b The ratio of the actual mass flow rate through a component, such as a steam nozzle, to the theoretical mass flow rate if the expansion process were isentropic, is referred to as the coefficient of discharge. This is an essential characteristic in fluid dynamics and thermodynamics. Comments Active