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S.No Question Option A Option B Option C Option D Answer Solution Comments Status Action
1 In reaction turbine Kinetic energy is appreciable as the fluid leaves the runner and enters draft tube The vanes are partly filled Total energy of fluid is converted to kinetic energy in the runner It is not exposed to atmosphere cancelled by SSC • The principal feature of a reaction turbine that distinguishes it from an impulse turbine is that only a part of the total head available at the inlet to the turbine is converted to velocity head before the runner is reached
• Also, in the reaction turbines the working fluid, instead of engaging only one or two blades, completely fills the passages in the runner.
• The pressure or static head of the fluid changes gradually as it passes through the runner along with the change in its kinetic energy based on absolute velocity due to the impulse action between the fluid and the runner.
• The pressure at the exit of the runner of a reaction turbine is generally less than atmospheric pressure, so the water at exit cannot be directly discharged to the tail race. The draft tube is a conduit which connects the runner exit to the tail race. The primary function of the draft tube is to reduce the velocity of the discharged water to minimize the loss of kinetic energy at the outlet. This permits the turbine to be set above the tail water without any appreciable drop of available head		 Comments Active
2 The specific speed of a turbine is the speed of such a turbine, identical with a given turbine, which Develops unit power under unit head Develops unit power under unit discharge Develops unit speed under unit head Delivers unit discharge under unit head a \(N_{s}=\frac{NP}{H^{\frac{5}{4}}}\)
Where, P= power, H=head, N= speed in rpm
The speed of an imaginary turbine which is identical with a certain given turbine, can develop a unit power under a unit head.		 Comments Active
3 The figure given below shows the relationship between power (P) and discharge (Q) for different vane exit angles of centrifugal pump. In the figure given below, curve B holds good for.
 Vane exit angle of 90áµ’ Vane exit angle of less than 90áµ’ Vane exit angle of more than 90áµ’ Any vane exit angle a
Comments Active
4 Low specific speed of turbine implies it is Propeller turbine Francis turbine Impulse turbine None of these c Range of Specific speed is given below:
Pelton turbine 9-30
Francis turbine 51-225
Kaplan or propeller turbine 255-860		 Comments Active
5 Head developed by a centrifugal pump depends on _____. Impeller diameter Speed Fluid density Both impeller diameter and speed d The head developed by the centrifugal pump depends upon impeller diameter and speed (increase) with both), although the impeller majorly gives kinetic energy to flow, which is then converted to pressure energy or (head) in the casing.
\(H∝N^{2}D^{2}\)		 Comments Active
6 In order that flow takes place between two points in a pipeline, the differential pressure between these points must be more than Frictional force Viscosity Surface friction All option are correct d For the flow to occur between two points in a pipeline the differential pressure between these points should be more than
Surface friction
Viscosity force
Frictional force
So that the pressure force of fluid can overcome the surface friction, viscous effects and frictional resistances allowing the flow to take place in a pipeline between any two points in a pipeline.		 Comments Active
7 The length of divergent portion of venturimeter in comparison to convergent portion is Same More Less More or less depending on capacity b The length of divergent portion of venturimeter in comparison to convergent portion is more due to avoid flow separation. Comments Active
8 Non uniform flow occurs when The direction and magnitude of the velocity at all points are identical The velocity of successive fluid particles, at any point, is the same at successive periods of time The magnitude and direction of the velocity do not change from point to point in the fluid Velocity, depth, pressure etc. change from point to point in the fluid flow d Uniform flow is defined as the type of flow in which the velocity at any given time does not change with respect to space.
\((\frac{∂V}{∂s})_{t=const}=0\)
Non – Uniform flow is defined as the type of flow in which the velocity at any given time changes with respect to space.
\((\frac{∂V}{∂s})_{t=const}≠0\)
When the velocity and other hydrodynamic parameters changes from one point to another the flow is defined as non-uniform.		 Comments Active
9 The stream function is observed for a two dimensional flow field What is the magnitude of the velocity at point (1, -1)? \(ψ=x^{3}-y^{3}\) 4.24 2.83 0 -2.83 a We know that –
\(u=-\frac{∂Ψ}{∂y} and v=\frac{∂Ψ}{∂x}\)
Given \(Ψ=x^{3}-y^{3}\)
\(u=3x^{2} and v=3y^{2}\)
At point (1,-1)
\(u=3 and v=3\)
Magnitude of velocity –
\(V=u^{2}+v^{2}\)
\(V=3^{2}+3^{2}\)
\(V=18\)
\(V=4.24 unit\)		 Comments Active
10 Which of the following advantages is/are possessed by a Kaplan turbine over a Francis turbine?
1. Low frictional losses
2. Part load efficiency is considerable high
3. More compact and smaller in size
Options		 Only 1 1 and 2 2 and 3 1, 2 and 3 d The Kaplan turbine is a type of axial flow turbine that is specifically designed for low to medium head hydropower plants. It is known for its efficiency and flexibility in operating at varying flow rates. One of the advantages of the Kaplan turbine over the Francis turbine is its low frictional losses. The adjustable blades of the Kaplan turbine allow for better control of the flow of water, reducing the frictional losses and improving the overall efficiency of the turbine. This results in higher energy conversion and lower energy losses compared to the Francis turbine. Another advantage of the Kaplan turbine is its high part load efficiency. The adjustable blades of the Kaplan turbine allow it to maintain a high efficiency over a wide range of operating conditions, including lower flow rates or loads. This means that even at partial loads, the Kaplan turbine can still operate efficiently and generate power effectively. Comments Active
11 Which one of the following conditions will linearize the Navier – Stokes equations to make it amenable for analytical solutions? Low Reynolds number (Re ≪ 1) High Reynolds number (Re ≫1) Low Mach number (M≪ 1) High Mach number (M≫ 1) a Navier Stokes Equation:
\(ρ\frac{DV}{Dt}=+∇p+ρg+μ∇^{2}V\)
Reynolds number is the ratio of inertia force to viscous force.
For flow at low Reynolds number, the inertia terms in the Navier-Strokes equations become small as compared to viscous terms. As such, when the inertia terms are omitted from the equations of motion, the analyses are valid for only Re < < 1.
Consequently, this approximation linearizes the Navier-Stokes equations and for some problems, makes it amenable to analytical solutions.
\(-∇p+μ∇^{2}V=0\)		 Comments Active
12 What is the unit of dynamic viscosity of a fluid termed ‘poise’ equivalent to? dyne/cm2 gs/cm dyne – s/cm2 g – cm/sec c Poise is a C.G.S. unit of dynamic viscosity equivalent to dyne sec/cm2
1 Poise is = 1dyne sec /cm2
= 10-5+4 N sec /m2
= 10-1 N sec/m2
= 0.1 N sec/m2		 Comments Active
13 Centrifugal pumps have which of the following advantages?
1. Low initial cost
2. Compact, occupying less floor space
3. Easy handling of highly viscous fluids		 1, 2 and 3 1 and 2 1 and 3 2 and 3 a Centrifugal pumps
Reciprocating pumps
The discharge is continuous and smooth
The discharge is fluctuating and pulsating
It can handle a large quantity of liquid
It handles a small quantity of liquid only
It can be used for lifting high viscous liquids like paper pulp, mud, sewage, etc.
It is used only for lifting highly viscous liquids.
It is used for large discharge through smaller heads
It is meant for a small discharge and high heads
Cost of a centrifugal pump is less as compared to reciprocating pump
Cost of a reciprocating pump is approximately four times the cost of a centrifugal pump.
Centrifugal pump runs at high speed. They can be coupled to an electric motor
It runs at low speed. Speed is limited due to consideration separation and cavitation
The operations of a centrifugal pump is smooth and without much noise. The maintenance cost is low
The operation of a reciprocating pump is complicated and with much noise. The maintenance cost is high.
It requires a smaller floor area and installation cost is low
It requires a larger floor area and installation cost is high
Efficiency is low
Efficiency is high		 Comments Active
14 Match List I with List II and Select the correct answer using the codes given below the lists.
List - I
List – II		 A – 2, B – 4, C – 1, D – 3 A – 3, B – 4, C – 1, D – 2 A – 2, B –1, C – 4, D – 3 A – 3, B – 1, C – 4, D – 2 d Lubrication – It is the method of decreasing friction between two solid bodies which are in contact. Most important property for lubrication is viscosity. Rise of Sap in trees – is the example of capillarly action.
Formation of Droplets – Due to surface tension liquid always tries to minimise their area.
Cavitation – Cavitation occurs to vapour formation.		 Comments Active
15 Pseudo plastic is a fluid for which dynamic viscosity decreases as the rate of shear increases Newton’s law of viscosity holds good dynamic viscosity increases as the rate of shear increases dynamic viscosity increases with the time for which shearing forces are applied a Fluids for which the flow behavior index n is less than unity are called Pseudo plastic.
The viscosity coefficient is smaller at a greater rate of velocity gradient and the curve becomes flatter as the shear rate (velocity gradient) increases.
These are known as shear thinning elements whose viscosity decreases under shear strain.
 Comments Active
16 The unit power of a turbine is equal to \(\frac{P}{H^{\frac{5}{2}}}\) \(\frac{P}{H^{\frac{1}{2}}}\) \(\frac{P}{H^{\frac{3}{2}}}\) \(\frac{P}{H^{\frac{2}{5}+\frac{1}{2}}}\) c In the speed, discharge, and power developed by a turbine under a head are known, then by using unit quantities the speed, discharge, and power developed by the same turbine under a different head can be obtained easily.
They are as follows:
\(Nu=\frac{N_{1}}{H_{1}}=\frac{N_{2}}{H_{2}}\)
\(Q_{u}=\frac{Q_{1}}{H_{1}}=\frac{Q_{2}}{H_{2}}\)
\(P_{u}=\frac{P_{1}}{H13/2}=\frac{P_{2}}{H23/2}\)		 Comments Active
17 Which one of the following is an axial flow turbine? Pelton wheel Francis turbine Kaplan turbine None of these c Impulse Turbine: If at the inlet of the turbine, the energy available is only kinetic energy, the turbine is known as impulse turbine. e.g. a Pelton wheel turbine.
Reaction Turbine: If at the inlet of the turbine, the water possesses kinetic energy as well as pressure energy, the turbine is known as a reaction turbine. e.g. Francis and kaplan turbine.
Tangential flow turbines: In this type of turbines, the water strikes the runner in the direction of the tangent to the wheel. Example: Pelton wheel turbine.
Radial flow turbines: In this type of turbines, the water strikes in the radial direction. Accordingly, it is further classified as:
Inward flow turbine: The flow is inward from periphery to the centre (centripetal type); Example: old Francis turbine
Outward flow turbine: The flow is inward from periphery to the centre (centripetal type); Example: Fourneyron turbine
Axial flow turbine: The flow of water is in the direction parallel to the axis of the shaft.
Example: Kaplan turbine and propeller turbine.		 Comments Active
18 The wave produced due to surface tenison in a shallow channel is known as gravity wave capillary wave elastic wave None of these b A capillary wave is a wave traveling along the phase boundary of a fluid, whose dynamics and phase velocity are dominated by the effects of surface tension. Comments Active
19 The maximum velocity of an airplane in steady level flight will occur at an angle of attack of 20.5ᵒ 18.5ᵒ 22.5ᵒ 26.5ᵒ b The angle of attack (AOA) is the angle at which the chord of an aircraft’s wing meets the relative wind. The chord is a straight line from the leading edge to the trailing edge. At low angles of attack, the airflow over the top of the wing flows smoothly and produces lift with a relatively small amount of drag.

As the AOA increases, both lift and drag increase; however, above a wing’s critical AOA, the flow of air separates from the upper surface and backfills, burbles and eddies, which reduces lift and increases drag. This condition is a stall, which can lead to loss of control and an abrupt loss of altitude if the AOA is not reduced.		 Comments Active
20 The coefficient of friction in term or Reynold’s number is 16/Re 32/Re 8/Re 10/Re a Darcy Weisbach Equation for friction looses in circular pipe:
\(h_{f}=\frac{4f×L×V^{2}}{2×g×D}\)
Where,
\(L=length of the pipe,\)
\(D=diameter of the circular pipe,\)
\(V=mean velocity of the flow,\)
\(f=Darcy^{'}s friction factor=4×C_{f}\)
\(C_{f}=Coefficient of firction\)
\(h_{f}=head loss due to friction\)
For Laminar Flow
Friction Factor \(f=\frac{64}{R_{c}} and C_{f}=\frac{1}{4}×\frac{64}{R_{c}}=\frac{16}{R_{c}}\)		 Comments Active
21 According to Nikuradse’s the boundary behaves hydrodynamically smooth when (k/δ)>10 (k/δ)>0.25 (k/δ)<0.25 (k/δ)<8 c Hydro – dynamically smooth: If the average height of irregularities (k) is much lesser than the thickness of he laminar sub-layer (), then the boundary is called hydro-dynamically smooth. \(δ\)
Hydro-dynamically rough:If the average height of irregularities (k) is much greater than the thikness of the laminar sub-layer (), then the boundary is called hydro-dynamically rough. \(δ\)
According to NIKURDE’s Experiment, the boundary is classified as:
Hydrodynamically smooth when \(\frac{k}{δ}<0.25\)
Boundary transition condition, when \(0.25<\frac{k}{δ}<6\)
Hydrodynamically rough when \(\frac{k}{δ}<6\)		 Comments Active
22 The discharge through a pipe can be measured with a venturimeter an orificemeter a flow nozzle All option are correct d A venturimeter is a device used for measuring the rate of a flow of a fluid flowing
through a pipe. It works on the Venturi effect which states that there is a reduction in fluid pressure when a fluid flows through a constricted section (or choke) of a pipe.
Orifice-meter is also used to measure the flow rate of the fluid. It works on the principle that the reduction of a cross-section of the following stream in passing through orifice
Increases the velocity head at the expense of pressure head. The only differece in Venturi and Orifice is that area reduction is gradual in a Venturi and its sudden in the orifice.
Flow Nozzle is a device used to measure the flow rate of fluids in a pipe or conduit. A flow nozzle consists of a cone-shaped passage that creates a partial blockage of the conduit, and the flow rate is determined by measuring the fluid pressure before and after the flow nozzle.		 Comments Active
23 The metacentric height of sailing ships is 0.45 m to 1.25 m 1.5 m to 3.5 m 0.25 m to 0.35 m 5 m to 7.5 m a In actual practice, an optimum value of metacentric height is selected and specified for the ship. The normal values for different ships are:
(i) Merchant ships: 0.3 to 1m
(ii) Sailing ships: 0.45 to 1.25 m
(iii) Battleships: 1.0 to 1.5 m
(iv) River crafts: up to 3.5 m		 Comments Active
24 The intensity of pressure in a liquid due its depth will, vary with depth: directly indirectly Both directly and indirectly None of these a According to Hydrostatic Law, the rate of increse of pressure in a vertical direction is equal to weight density of the fluid at that point when the fluid is stationary.

The pressrue at any point in a fluid at rest is obtained by the Hydrostatic Law which states that the rate of increase of pressrue in a vertically downward direction must be equal to the specific weight of the fluid at that point.
\( \frac{dP}{dh}=w for downward direction\)
\(\frac{dP}{dh}=-w in upward direction\)
Thus, pressure in a stationary water column increases with depth and varies linearly and does not depend upon viscosity.
It indicates that a negative pressrue gradient exists upward along any vertical.		 Comments Active
25 Surface tenison is caused by the force of _____ at the free surface. Cohesion adhesion both coheasion and adhesion None of these a Surface tension a line forced caused by cohesion of fluid paritcle at the surface, the property of cohesion enables a liquid to resist tensile stress.
Surface tension is due to cohesion between particles at the surface and Capillarity action is due to both cohesion and adhesion.		 Comments Active
26 Metacentric height is the distance between CG of body and centre of pressure CG of body and the metacentre CG of body and centre of buoyancy None of these b It is defined as the point about which a body starts oscillating when the body is tilted by a small angle.

The meta-centre may also be defined as the point at which the line of action of the force of buoyancy will meet the normal axis of the body when the body when the body is given a small angular displacement.
The distance MG i.e. the distance between the meta-centre of a floating body and the centre of gravity of the body is called metacentric height.
It is measured along with the line BG.		 Comments Active
27 The wetted perimeter for a pipe running full of water is equal to: Where d is the diameter of the pipe πd/2 2πd πd δ c The hydraulic mean depth or also called Hydraulic radius is defined as:
\(R=\frac{Wetted Area}{Wetted perimeter}\)
Wetted area, \(A=\frac{Ï€}{4}d^{2}\)
Wetted perimeter, P = d \(Ï€\)
Hydraulic radius, \(R=\frac{A}{P}\)
\(y_{m}=R=\frac{A}{P}=\frac{Ï€d^{2}}{4Ï€d}=\frac{d}{4}\)		 Comments Active
28 According to principle of floatation, the weight of liquid displaced as compared to the weight of the body is more less same depending upon the shape of the body c The principle of floatation states that the weight of the floating body is equal to the weight of the liquid displaced by the floating body. Comments Active
29 Any liquid flow, obeys the following Capillary action Bernoullis equation Continuity equation Newton’s law of viscosity c Continuity equation is based on mass conservation “ mass can neither be created nor be destroyed.” This is the basic condition of fluid flow. Ideal fluid does not posses viscocity, thus does not obeys neutons law of viscosity.
Q=AV		 Comments Active
30 The channel section considered to have the highest efficiency is Quadrant Square Trapezoid Triangular c The length of the channel bundary (sides and the base of the channel) which comes in contact with the flowing liquid is called the wetted perimeter.
The most efficient section must have a minimum wetted perimeter and hence minimum resistance to flow.
Compared to other cross-sections, the semicircular section has the lowest wetted perimeter, and is, therefore, the section of the highest efficiency, but, due to practical limitations in maintaining the section, trapezoidal channels are usually employd.
The hydraulic mean depth or Hydraulic radius is the ratio of the wetted area to the wetted perimeter.
Shape
Flow Area A
Wetted Perimeter, P
Hydraulic Radius Rh
Trapezoidal
Y (b + cot ) \(α\)
\(b+\frac{2y}{sinα}\)
\(\frac{y(b+ycotα)}{b+\frac{2y}{sinα}}\)
Triangular
\(y^{2}cotα\)
\(\frac{2y}{sinα}\)
\(\frac{ycosα}{2}\)
Rectangular
By
b +2y
\(\frac{by}{b+2y}\)
Wide flat
By
b
y
Circular
\((α-sinα)\frac{D^{2}}{8}\)
\(\frac{αD}{2}\)
\(\frac{D}{4}(1-\frac{sinα}{α})\)		 Comments Active
31 Efficiency of a Carnot engine is 75%. If the cycle direction is reversed, COP of the reversed Carnot cycle is 1.33 0.75 0.33 1.75 Cancelled by SSC Efficiency of carnot engine =0.75.
COP of reversed carnot cycle
For heat pump
COP of H.P =1/Efficiency of carnot engine =1/0.75 =1.33
For refrigerator
COP of refrigerator = COP of H.P -1 = 1.33-1
COP o refrigerator = 0.33		 Comments Active
32 A reversible engine operated between temperature T1 and T2. The energy rejected by this engine is received by a second reversible engine at temperature T2 and rejected to a reservoir at temperature T3. If the efficiencies of the engines are same then, the relationship between T1, T2 and T3 is given by T2 = (T1+T3)/2 T2 = sqrt ((T1)2 + (T3)2) T2 = sqrt (T1 × T2) None of these c When efficiencies of the engine are same \(T_{3}=T_{1}×T_{2}\)
When Workdone is same \(T_{3}=\frac{T_{1}+T_{2}}{2}\)		 Comments Active
33 The heat tranfer Q, the work done W and the change in internal energy U are all zero in the case of a rigid vessel containing steam at 150áµ’C left in the atmosphere which is at 25áµ’C 1 kg of gas contained in an insulated cylinder expanding as the piston moves slowly outwards. a rigid vessel containing ammonia gas connected through a valve to an evacuated rigid vessel, the vessel, the valve and the connecting pipes being well insulated and the valve being opened and after a time, condition through the two vessels becoming uniform 1 kg of air flowing adiabatically from the atmosphere into a previously evacuated bottle c In first option, there is heat transfer because of temperature difference.....in second option as container is insulated so no heat transfer but due to expansion there will be work transfer....3rd option as there container is insulated there will be no heat transfer and also expansion is against vacuum so there will no work tansfer. Comments Active
34 The solid fuel having the highest calorific value is wood lignite coke anthracite d High rank coal used for industrial and residential applications. It has generally less than 10% volatile matter and a high carbon content (about 90% fixed carbon). Its gross calorific value is equal to or greater than 24 000 kJ/kg on an ash-free but moist basis. Comments Active
35 The volume of the universal gas constant (Ru) is equal to 848 m kgf.kg-mol/K 8.48 m kgf/kg-mol/K 84.8 m kgf.kg-mol/K 0.848 m kgf/kg-mol/K a The universal gas constant or molar constant (Ru) of a gas is the product of the specific gas constant (R) and the molecular mass of the gas (M). The S.I. unit of Ru is 8.314 kJ/kg – mol K(or 8314 J/kg – mol K). M.K.S unit of Ru is 848 kgf -m/kg mole - K (Note 1 kgf-m = 9.81 joules). Comments Active
36 Liquids have No specific heat different values of specific heat at same temperature only one value of specific heat two distinct vlaues of specific heat c Specific heat of a substance is defined as the amount of heat required to raise the temperature of a unit mass of any substance thorugh one defree. SI unit of specific heat is kJ/kg/K.
Since solids and liquids are considered as incompressible, therefore they have only one specific heat. But gases have two specific heats depending upon the process i.e. specific heat at constant pressrue and specific heat at constant volume.		 Comments Active
37 A refrigeration system works on second law of thermodynamics first law of thermodynamics zeroth law of thermodynamics None of these a A refrigerator and heat pump both works on Clausius' statement of second law of thermodynamics.
Clausius' statement of the second law states that,"It is impossible to transfer heat in a cyclic process from low temperature to high temperature without work from an external source".		 Comments Active
38 Centrifugal pump is an example of isolated system closed system steady flow system None of these c ï‚· in a steady flow system, the mass and energy entering and leaving the system remain constant over time.
 a centrifugal pump continuously draws in fluid at the inlet and discharges it at the outlet — under steady operating conditions, the flow parameters (like pressure, velocity, and mass flow rate) do not change with time at any specific location.
ï‚· the pump operates with continuous flow, assuming constant speed and operating conditions.		 Comments Active
39 In metric system the unit of heat is given as CHU BTU kcal Kelvin c In the metric system, the unit of heat is typically expressed as:
Kcal – kilocalorie1 kilocalorie = 1000 calories
This is a metric unit used to measure the amount of heat energy. It's defined as the amount of heat required to raise the temperature of 1 kilogram of water by 1°C at standard atmospheric pressure.		 Comments Active
40 The bomb calorimeter is an apparatus to measure the calorific value of a gaseous fuel calorific value of solid and gaseous fuels calorimetric composition of any solid bomb material calorific value of a solid or liquid fuel d The Bomb Calorimeter  was used to measure the gross calorific value of the solid and liquid samples. It is a constant-volume type calorimeter that measures the heat of a particular reaction or measures the calorific value of the fuels. Comments Active
41 Which of the following statements is true? Crater wear is predominant in ceramic tools Crater wear is predominant in carbon tool steel Crater wear is predominant in high speed steel tools Crater wear is predominant in tungsten carbide tools d • In the machining process, the wearing action takes place on those surfaces along which there is relative sliding with other surfaces.
• On the rake surface, the wear takes place because of the movement of the chip over the tool, and over the flank surface, the wear takes place because of rubbing action between the tool and the workpiece.
• The wear overrake surface is known as crater wear and over flank, the surface is known as flank wear.
• Crater wear occurs on the rake face. For the crater wear, the temperature is the main culprit and tool diffuses into the chip material and the tool temperature is maximum at some distance from the tooltip. So crater wear starts at some distance from the tooltip.
• Crater wear is more predominant in Tungsten carbide tools because when the interface temperature is high then the carbides disintegrate (WCdisintegrate into W and C) and carbon diffuses to the softer matrix of the machining part.
• This phenomenon reduces the strength of the tool and after some time it dislodges it.		 Comments Active
42 The process of enlarging a hole is known as counter boarding counter sinking boring drilling c Boring: Boring is the process of enlarging a pre-existing hole, which could have been formed by a drill or by a casting's core using a single-point cutting tool.
• Making the hole concentric with the work piece's axis of rotation may be an equally significant and concurrent objective of boring. This would correct any eccentricity that might have occurred as a result of the drill diverting off the centerline. One crucial characteristic of drilled holes is concentricity.		 Comments Active
43 Thermite is a mixture of aluminium and iron oxide in the ratio of 3:1 iron and aluminium oxide in the ratio of 3:1 aluminium and iron oxide in the ratio of 3:1, with traces of sulphur, phosphorus and maganese molten iron and aluminium, with the ratio depending upon the type of the surface to be welded a It is a welding process utilizing heat generated by an exothermic chemical reaction between the components of the thermit (a mixture of metal oxide and aluminium powder). In this process, fine aluminium particles and metal oxide are mixed in and ignited by an external heat source.
The reaction will proceed according to the following equation:
Metal Oxide + Aluminum - Aluminum Oxide + Metal + Heat
Thermit Welding is mainly used for joining steel parts. It is used for repair of steel casings and forgings, for joining railroad rails, steel wires and steel pipes, for joining the large cast and forged parts. For which aluminium is mixed with the iron oxide in the ratio of 1:3 by weight.
3Fe3O4+8Al 9Fe + 4Al2O3 + (Heat) \(→\)		 Comments Active
44 Generally, the strongest form in which metals can be used as hot rolling cold rolling extrusion forging b Rolling: It is the deformation process of a metal that is widely used in the metal forming process. It is done by passing the strip of the metal between the pair of rollers. The thickness is gradually decreased. The cross-section area will be changed but the volume remains constant.

It is classified into two types:
• Cold rolling
• Hot rolling
Cold rolling produces strongest components.		 Comments Active
45 An optical gauge works on the principle of reflection of light rays polarisation of light rays interference of light rays refraction of light rays c Optical gauges — such as interference-type optical comparators — work on the principle of interference of light. These instruments use interference fringes generated by the interaction of coherent light waves to measure small displacements or dimensions with very high precision (in the order of microns or even nanometers). Comments Active
46 Plain and butt welds may be used on materials upto approximately 25 mm thick 40 mm thick 50 mm thick 75 mm thick a Plain and butt welds are simple and effective for materials up to 25 mm thick. for thicker materials, more sophisticated methods, like groove welds or fillet welds, are used to achieve the necessary joint integrity and strength. Comments Active
47 The bonding of a rubber sheet with a metal is done by Welding High frequency dielectric heating Induction welding Adhesive bonding d Rubber sheets are commonly bonded with metal surfaces through adhesive bonding, which involves the use of a special adhesive material that bonds the rubber to the metal. This method is widely used due to its simplicity and effectiveness in creating a strong bond between different materials, such as rubber and metal.
Welding typically applies to metals and involves melting and fusing the materials together, which isn't suitable for rubber.
High-frequency dielectric heating and induction welding are processes primarily used for heating materials and welding metals or other conductive materials, not for bonding rubber to metal.		 Comments Active
48 ______ iron is the magnetic allotrope of iron. α β γ δ a -iron is the magnetic allotrope of the iron. The -iron also called ferrite is an interstitial solid solution of carbon in -iron which is a pure form of iron having BCC structure with an average number of atoms 2 and having a magnetic character up to 768 and above 768 is non-magnetic. \(α\) \(α\) \(α\) \(℃\) \(℃\) Comments Active
49 Monel metal is an alloy of Cu and Cr Ni and Cu Ni and Cr Cu, Ni and Cr b Properties of Monel Metal:
It is an important alloy of nickel and copper.
It contains 68% nickel, 29% copper, and 3% other constituents like iron, manganese, silicon, and carbon.
It resembles nickel in appearance and is strong, ductile, and tough.
It is superior to brass and bronze in corrosion-resisting properties.
It is used for making propellers, pump fittings, condenser tubes, steam turbine blades, sea water exposed parts, tanks, and chemical and food handling plants.		 Comments Active
50 With which of the following age hardening is related? Cast iron Gun metal Duralumin German silve c Age Hardening- The process of returning the super-saturated solid solution to a more stable condition in the solid-state during the passage of time is called ageing. If the material hardness and strength increase with ageing, this is called age hardening, lowering the temperature impedes ageing.
There are two types of Ageing:
Natural Ageing - If the ageing hardening is carried out at room temperature, it is called natural ageing. In natural ageing, there is no decomposition of any phase but the accumulation of solute atoms occurs at the grain boundaries which makes slipping hard and thus increases the hardness and strength. Since no decomposition, hence no loss of ductility, dislocations are hampered due to accumulation.
Artificial Ageing - When the alloy is subjected to elevated temperature, the decomposition takes place and solute atoms concentrate at the site where there is an increased concentration of solute atorms. This distorts the lattice of the alloy and hardens. Artificial ageing is faster than natural ageing.
Effect of temperature on Ageing:

Ageing is accelerated at elevated temperature: As the temperature increases ageing increases. As the graph shows that after a period of time, the hardness of alloy goes on decreasing. This is called over ageing.
Age hardening increases the yield strength of malleable materials, including most structural alloys of aluminium, magnesium, nickel, titanium, and some steels and stainless steels.		 Comments Active
51 For a gas with n degree of freedom, what will be the value of ? \(\frac{C_{p}}{C_{v}}\) n + 1 n – 1 1-2/n 1+2/n d For a gas with n degree of freedom, what will be the value of is . \(\frac{C_{p}}{C_{v}}\) \(1+\frac{2}{n}\) Comments Active
52 What type of slopes does constant pressure line have in the superheated region of the Mollier diagram? Positive slope Negative slope Zero slope First positive than negative slope a In superheated regions, constant pressure lines diverge, because with increasing temperature, the slope increases.so constant pressure line has positive slope in the superheated region Comments Active
53 If two Carnot engine CE1 and CE2 are connected in a series such that the heat rejected by CE1 is used as the input for the CE2 cycle with the intermediate temperature being the geometric mean of the extreme temperature. Which of the following statement is TRUE for this efficiency of the Carnot engine? \(η_{CE1}>η_{CE2}\) \(η_{CE1}<η_{CE2}\) \(η_{CE1}=η_{CE2}\) Insufficient data c
\(η_{CE1}=1-\frac{T_{2}}{T_{1}}=1-\frac{T_{1} T_{3}}{T_{1}}=1-\frac{T_{3}}{T_{1}}\)
\(η_{CE2}=1-\frac{T_{3}}{T_{2}}=1-\frac{T_{3}}{T_{1} T_{3}}=1-\frac{T_{3}}{T_{1}}\)
\(η_{CE1}=η_{CE2}\)		 Comments Active
54 What happens to the COP of a heat pump, when the temperature difference between source and sink is decreased? Decreases First decreases, then increases First increases, then decreases Increases d The efficiency of the cycle is given as  . Here T1 is the temperature of the source and T2 is the temperature of the sink. If the difference between temperature of the source and the sink is increased (i.e. temperature of source increase or temperature of sink decreases), the T2/T1 value decreases and thus efficiency increases. \(=1-\frac{T2}{T1}\) Comments Active
55 2500 kJ/min heat is supplied to a heat engine at 727ᵒ(C) It rejects heat at 900 kJ/min at 223ᵒ(C) This type of engine is _______. ideal irreversible impossible practical c \(η_{carnot}=η_{max}=1-\frac{T_{L}}{T_{H}}=1-\frac{496}{1000}=50.4%\)
\(η_{engine}=1-\frac{Q_{L}}{Q_{H}}=1-\frac{900}{2500}=64%\)
Engine efficiency cannot be greater than carnot efficiency, So cycle is impossible.		 Comments Active
56 The internal energy of the system is a function of temperature only U = 30 + 0.5t kJ. If the system does the work of 0.5 kJ/K. What is the increase in heat interaction per degree temperature? – 1 0 1 Cannot be determind c According to the first law of thermodynamics
\(∂Q=∆U+∂W\)
=0.5KJ/K \(\frac{∆U}{∆t}\)
\(\frac{∂Q}{∂t}=\frac{∆U}{∆t}+\frac{∂W}{∂t}\)
\( ∂Q=0.5+0.5=1KJ/K\)		 Comments Active
57 Specific enthalpy is an _______ of a system and its unit is _____. extensive property, kJ extensive property, kJ/kg intensive property, kJ intensive property, kJ/kg d Specific enthalpy (enthalpy per unit mass) is an intensive property and its unit is kJ/kg Comments Active
58 A reversible adiabatic in a T – S diagram is a ______. point vertical line horizontal line parabolic curve b A Reversible adiabatic is known as an isentropic process (entropy constant). So, it will be represented by a vertical line on T – S diagram. Comments Active
59 The work done by a system is 45 kJ. If the internal energy of the system in decreased by 15 kJ. What is the heat received (in kJ). What is the heat received (in kJ) by the system? – 60 – 30 30 60 c Given
\( ∂W=45kJ and ∆U=-15\)
\(∂Q=∆U+∂W=-15+45=30kJ\)		 Comments Active
60 Which of the following graphs represents working of an ideal Diesel cycle on p – V Scale? a Diesel cycle consist of:
Process 1 – 2 = Reversible adiabatic compression.
Process 2 – 3 = Constant pressure heat addition.
Process 3 – 4 = Reversible adiabatic expansion.
Process 4 – 1 = Constant volume heat rejection.		 Comments Active
61 In a P – T diagram for pure substance, the melting line has highest inclination with respect to the positive horizontal axis representing temperature for which type of substance? Substance that contracts on freezing Substance that expands on freezing Substance that has same volume on freezing None of these b Comments Active
62 Which equation represents the steady flow system? \(H_{1}+\frac{V12}{2gJ}+\frac{z_{1}}{J}+Q=\frac{V22}{2gJ}+\frac{z_{2}}{J}+Losses\) \(H_{1}+\frac{V12}{2gJ}+\frac{z_{1}}{J}+Q=\frac{V22}{2gJ}+\frac{z_{2}}{J}+Losses+Workdone\) \(H_{1}+\frac{V12}{2gJ}+\frac{z_{1}}{J}+Q=H_{2}+\frac{V22}{2gJ}+\frac{z_{2}}{J}+Losses+Workdone\) \(H_{1}+\frac{V12}{2gJ}+\frac{z_{1}}{J}=H_{2}+\frac{V22}{2gJ}+\frac{z_{2}}{J}+Losses+Workdone\) c If there is no accumulation of energy in the control volume then by the conservation of energy, the total rate of flow of all energy steams entering must be equal to the total rate of flow of all energy streams leaving the control volume.
This may be expresses.
\(h_{1}+\frac{v12}{2}+z_{1}g+\frac{dQ}{dm}=h_{2}+\frac{v22}{2}+z_{2}g+\frac{dW}{dm}\)
\(H_{1}+\frac{V12}{2g}+z_{1}+Q=H_{2}+\frac{V22}{2g}+z_{2}+Losses+Workdone \)		 Comments Active
63 For a process which is non – flow (U is the internal energy, Q is the heat and W is the work done) the first law of thermodynamics states ______. \(∂U=∂Q-∂W\) \(dQ+dW=0\) \(dQ≠dW\) \(∂U=∂Q\) cancelled by SSC first law of thermodynamics, \(∆U=∂Q-∂W\) Comments Active
64 What happens to the efficiency, when the temperature of intake air is lowered in an I.C engine? Increases Decreases Remains same Increases to a certain limit, then decreases cancelled by SSC Consider Otto cycle:

\(η=1-\frac{T_{1}}{T_{2}}=1-(\frac{V_{2}}{V_{1}})^{γ-1}=1-\frac{1}{r^{γ-1}}\)
So, when the temperature of intake air is lowered i.e. is lowered, the efficiency of IC engine will increase. \(T_{1}\)		 Comments Active
65 Which of the engine has a spark plug used for ignition the fuel? Petrol engine Diesel engine Steam engine Gas engine a Petrol engine or gasoline engine is a spark ignition, designed to run on petrol and similar volatile fuels. In petrol engines, the fuel and air are usually pre-mixed before compression, whereas in Diesel (compression ignition) engines, ignition of the fuel is caused by the elevated temperature (due to adiabatic compression of air). Comments Active
66 Which equation best represents the net entropy changes for an irreversible process? s = 0 s = 1 s < 0 s > 0 d Entropy can never be decreases for an irreversible process. Comments Active
67 A Carnot heat pump is used to maintain a room at a temperature of 30áµ’C, the initial temperature of the room was 30áµ’C if the power requirement of the pump is 20 kW. What is the heat pumped (in kW) to the room? 3 17 154 174 Cancelled by SSC (COP) of heat pump= \(\frac{T_{1}}{T_{1}-T_{2}}\)
\(\frac{20}{W_{in}}=\frac{300}{300-269}\)
\(W_{in}=\frac{20×31}{300}=2.066KW\)		 Comments Active
68 The entropy change of the system and the surroundings during a process between two equilibrium states is ______. Equal to zero Greater than zero Less than zero Greater than or equal to zero d The entropy of an isolated system during a process always increases or, in the limiting case of a reversible process, remains constant. In other words, it never decreases. This is known as the increase of entropy principle.
\(∆S=\frac{δQ}{T}+S_{gen}\)
\(∆S≥0\)		 Comments Active
69 Which equation clearly defines the entropy change during the isothermal process for a , volume , Temperature and entropy is heated to state points of pressure , volume , temperature and entropy ? \(P_{1}\) \(V_{1}\) \(T_{1}\) \(S_{1}\) \(P_{2}\) \(V_{2}\) \(T_{2}\) \(S_{2}\) \(mc_{v}In\frac{T_{2}}{T_{1}}\) \(mc_{p}In\frac{T_{2}}{T_{1}}\) \(mRIn\frac{V_{2}}{V_{1}}\) \(mc_{v}(\frac{n-γ}{n-1})In\frac{T_{2}}{T_{1}}\) c \(S_{2}-S_{1}=mRIn\frac{V_{2}}{V_{1}}\) Comments Active
70 In a P – V diagram for pure substance, the constant temperature line in superheated region is ______. Converging Diverging Intersecting Parallel b In a P-V diagram for a pure substance, the constant temperature line in the saturated liquid-vapor region is parallel whereas, in the superheated region, these lines are diverging. Comments Active
71 Choose the CORRECT equation which defines the relationship between the Young’s Modulus (E), Bulk modulus (K) and Poisson’s ratio (u). E = 3K(1-2u) E = 3K(1-u) K = 3E(1-2u) K = 3E(1-u) a The relationship between the Young’s Modulus (E), Bulk modulus (K) and Poisson’s ratio (u) is E = 3K (1-2u) Comments Active
72 A cross sectional bar of area 700 mm2 is subjected to an axial load as shown in the figure below. What is the value of stress (MPa) in the section QR?
 30 40 50 60 b Consider a section in PQ, QR and RS segment respectively and find the load acting on these segments by the algebraic sum of loads on either side of the section considered.
PPQ = 63 KN, PQR = 63-35 = 28 kN, PRs = - 21 kN
Free body diagram of different segments shown below,

Now for the bar QR
\(σ_{QR}=\frac{P_{QR}}{A}=\frac{28×1000}{700}=40 MPa\)		 Comments Active
73 Calculate the total angle of twist for a stepped shaft which is subjected to the torque (T) are shown in the figure below.
 \(\frac{TI}{πGd^{4}}\) \(\frac{66TI}{πGd^{4}}\) \(\frac{TI}{66Gd^{4}}\) \(\frac{36TI}{πGd^{4}}\) b \(\frac{T}{J}=\frac{Gθ}{l}, θ=\frac{Tl}{GJ}\)
Total angle of twist \(θ=θ_{1}+θ_{2}, \)
\(Tl/[\frac{GÏ€(2d)^{4}}{32}\)+T2l/[\frac{GÏ€d^{4}}{32}]]
= \(\frac{2Tl}{GÏ€d^{4}}+\frac{64Tl}{GÏ€d^{4}}=\frac{66Tl}{GÏ€d^{4}}\)		 Comments Active
74 Consider the loaded beam as shown in the figure below
 None of these a & c both Comments Active
75 The property of a material states that it is rigid the value of Poisson’s ratio for this particle is ____________. 0 1 2 None of these a For a rigid body, the value of Poisson's ratio is zero. A zero Poisson's ratio means that there is no transverse deformation resulting from an axial strain. Comments Active
76 The elongation (mm) in a steel bar having a square cross section of dimension 40 mm × 40 mm is 2.5 mm and is subjected to an axial compressive load of P (kN). If the length of the bar is 4 m and modulus of elasticity is E = 250 GP(a) What is the value of P (kN)? 100 150 200 250 d given Elongation =2.5mm, area A=40 mm × 40 mm, length of bar l=4m=4 × 1000, modulus of elasticity E=250 GPa =250 × 1000Mpa \( ε\)
\(ε=(Pl)/(AE)\)
Load P==N \(\frac{2.5×40×40×250×10^{3}}{4×10^{3}}\) \(250×10^{3}\)
=250KN		 Comments Active
77 Determine the shape of the elastic curve between the supports B and C for the beam as shown in the figure below.
 A straight line Elliptical Parabolic Circular d
Bending moment BC = Constant
\(\frac{M}{I}=\frac{E}{R}=\frac{σ}{Y}\)
\(R=\frac{EI}{M}\)
M = constant R = Constant = Circle		 Comments Active
78 The formula for the Euler’s buckling load is given as this is TRUE for which of the following columns? \(\frac{π^{2}EI}{4L^{2}}\) Column with one end fixed and other end free Column with one end fixed and other end hinged Column with both ends fixed Column with both hinged ends a The formula for the Euler’s buckling load is= \(\frac{π^{2}EI}{le2}\)
For One end fixed and the other end free, the effective length will be=2l,
So that, Euler’s buckling load is \(\frac{π^{2}EI}{4L^{2}}\)		 Comments Active
79 Choose the INCORRECT conditions for the thermal stress in a body. It is the function of coefficient of thermal expansion It is the function of temperature rise It is the function of modulus of elasticity It is the function of modulus of rigidity d : \( σ_{t}=Eα∆t\)
Where, E= modulus of elasticity, coefficient of thermal expansion, \( α=\)
Temperature difference \( ∆t=\)		 Comments Active
80 A steel rod whose diameter is 2 cm and is 2 m long experiences heating from 30ᵒC to 150ᵒC The coefficient of thermal expansion is α = 12 × 10-6//ᵒC and the rod has been restricted in its original position. The thermal stress developed is 288 MPa What is the value of Young’s modulus (GPa)? 50 100 150 200 d \( σ_{t}=Eα∆t\)
Given α = 12 × 10-6//ᵒC,, \( σ_{t}=288Mpa\) \( ∆t=(150-30)\)
E== \( σ_{t}/(α×∆t)\) \(288/(12×10^{-6}×120)\)
= \(200×10^{3}Mpa=200Gpa\)		 Comments Active
81 Which of the following is CORRECT option for validation of Hooke’s law in simple tension test? Ultimate stress Breaking point Elastic limit Limit of proportionality d Hooke’s law states that stress is directly proportional to strain up to a certain point. This law holds true as long as the material remains within its elastic range.
The limit of proportionality is the point beyond which the material no longer obeys Hooke’s law. This is where the relationship between stress and strain is no longer linear.		 Comments Active
82 Calculate the value of modulus of elasticity (N/mm2), if the Poisson’s ratio is 0.25 and modulus of rigidity of the material is 80 N/mm? 100 200 250 300 b Given C=80 N/mm2, \(μ=0.25\)
, \(E=2C(1+μ)\) \(=2×80(1+0.25)\)
=200 N/mm2		 Comments Active
83 Which of the following statement is CORRECT for the modulus of resilience? It is the ratio of maximum stress energy and unit volume It is the ratio of maximum strain energy and unit volume It is the ratio of proof resilience and unit volume It is the ratio of proof resilience and unit area c Modulus of resilience is the maximum strain energy that a material can absorb without permanent deformation.
It is given by the area under the stress-strain curve up to the yield point.
It is expressed as the proof resilience per unit volume, not unit area or stress.		 Comments Active
84 Which of the given formula is CORRECT for calculating the angle of static friction? \(∅_{s}\) \(tan^{-1} μ_{s}\) \(sin^{-1} μ_{s}\) \( cos^{-1} μ_{s}\) None of these a The angle at which the resultant of force of limiting friction f and normal reaction R makes with the direction of normal reaction R is called the angle of friction.
Coefficient of static friction, \(μ=tanθ\)

In \(∆ROC tanθ=\frac{RC}{OR}=\frac{OB}{OR}=\frac{F}{R}=μ\)
Hence \(μ=tanθ\)		 Comments Active
85 Choose the option which is INCORRECT about the term friction. Friction produces heat It leads to the decrease in the velocity of object It leads to the increase in the velocity of object It can stop the moving object c Friction, force that resists the sliding or rolling of one solid object over another. Frictional forces, such as the traction needed to walk without slipping, may be beneficial, but they also present a great measure of opposition to motion. About 20 percent of the engine power of automobiles is consumed in overcoming frictional forces in the moving parts.
Friction is the resistance to motion of one object moving relative to another.
It produces heat
It opposes relative motion between two object which are in contact. Hence friction force always acts opposite to direction of motion.
It leads to decrease in velocity of object.
It depends on the nature of the surface.		 Comments Active
86 The tensile strength for the plate per pitch length of the outer row of the rivet is ________. \(P_{t}\frac{(p-d)tσ_{t}}{2}\) \(P_{t}=2(p-d)tσ_{t}\) \(P_{t}=(p-d)tσ_{t}\) \(P_{t}=(p-d)t^{2}σ_{t}\) c The tensile strength of the rivet per pitch length is. , where p=pitch, d= dia of rivet, t= thickness of plate \(P_{t}=(p-d)tσ_{t}\) Comments Active
87 The point of contact which is common between the two pitch circles is known as _____. Base point Addendum Dedendum Pitch point d "The pitch point is the point of tangency between the pitch circles of two meshing gears. At this point, pure rolling motion occurs, enabling smooth and uniform transmission of motion." Comments Active
88 The governor in which the displacement of the sleeve is high for the small change of speed in known as ___________. Hunting Sensitive Stable Isochronous b Sensitive Governor: If a governor is having a larger displacement of sleeve for a given fractional change of speed then it is known as sensitive governor. Comments Active
89 The profile of the gears in involute with 200. If the length of the path of approach and length of path of recess are 28 mm and 25 mm respectively. What is the length of arc of contact? (Cos 20áµ’ = 0.94) 54 54.4 56 56.4 d Given
\(∅=20°\)
\(L_{A}=28 mm\)
\(L_{R}=25 mm\)
POC = \(L_{A}+L_{R}=28+25=53 mm\)
Arc of contact \(=\frac{53}{cos20}=\frac{53}{0.94}=56.4\)		 Comments Active
90 Which of the following toothed wheels does not come under the classification according to the type of gearing? External gearing: the gears of the two shafts mesh externally with each other. The larger of these two wheels is called spur wheel or gear and the smaller wheel iscalled pinion. Internal gearing: the gears of the two shafts mesh internally with each other. The larger of these two wheels is called annular wheel and the smaller wheel is called pinion. Rack and pinion: "In rack and pinion, a circular pinion meshes with a straight-line toothed rack. It converts rotary motion to linear motion or vice versa. This is considered under the type of gearing." Parallel gearing d According to the type of gearing, gears are classified as: Comments Active
91 Which of the following theory is/are used for the determination of torque quantities in cone clutch? Uniform pressure theory Uniform strain theory Uniform stress theory None of these a For determining the torque two theories are used:
Uniform pressure theory
Uniform wear theory		 Comments Active
92 Which of the following statement is INCORRECT about the dry clutch and wet clutch? Heat dissipation is more difficult in dry clutch Rate of wear is very less in wet clutches as compared to dry clutches Torque transmitting capacity of dry clutch is less than wet clutch Engagement in wet clutch is smoother than dry clutch c ï‚· Inversion of a mechanism refers to getting different mechanisms from a single kinematic chain by fixing different links one at a time.
ï‚· The relative motion between the links remains the same, but the absolute motion and the application can change.
ï‚· This concept is foundational in mechanism design (e.g., slider-crank mechanism inversions).		 Comments Active
93 Which of the following condition is CORRECT about the inversion of a mechanism? Conversion of higher pair to lower pair Turning it upside down Obtained by fixing different links in a kinematic chain Obtained by reversing the input and output motion of the mechanism c This method of obtaining different mechanisms by fixing different links in a kinematic chain is known as inversion of the mechanism. In the process of inversion, the relative motions of the links of the mechanisms produced remain unchanged. Comments Active
94 Which of the following statement is CORRECT about the bull engine? Obtained by fixing the cylinder or sliding pair Obtaining by fixing the crank Obtaining by fixing the piston rod None of these a Inversions of the slider-crank mechanism is obtained by fixing links 1, 2, 3 and 4.
• First inversion: This inversion is obtained when link 1 (ground body) is fixed.
Application- Reciprocating engine, reciprocating compressor etc.
• Second inversion: This inversion is obtained when link 2 (crank) is fixed.
Application- Whitworth quick returns mechanism, Rotary engine, etc.
• Third inversion: This inversion is obtained when link 3 (connecting rod) is fixed.
Application - Slotted crank mechanism, Oscillatory engine etc.
•Fourth inversion: This inversion is obtained when link 4 (slider) is fixed.
Application- A hand pump, pendulum pump or Bull engine, etc.		 Comments Active
95 The power transmission takes place in shaft rotating at 400 rpm and this rotating shaft drives another shaft at 600 rpm. The smaller pulley has the diameter of 0.5 m. The centre distance between pulleys is 4m. If the angle of contact on the smaller pulley for the open belt drive is 1.8áµ’ then calculate the diameter of larger pulley (in mm) and angle of contract (in rad)? 0.50 and 2.00 0.75 and 2.00 0.50 and 3.08 0.75 and 3.08 d Given
\(N_{1}=400 rpm\)
\(N_{2}=600 rpm\)
\(∆_{2}=0.5 m\)
\(X=4m\)
\(θ_{2}=1.8°\)
\(\frac{N_{2}}{N_{1}}=\frac{∆_{1}}{∆_{2}}\)
\(∆_{1}=∆_{2} \frac{N_{2}}{N_{1}}\)
\(=0.5×\frac{600}{400}\)
\(∆_{1}=0.75 m\)
\(Sinα=\frac{r_{1}-r_{2}}{x}=\frac{∆_{1}-∆_{2}}{2x}=\frac{0.75-05}{2×4}=0.03125\)
\(α=1.79°\)
Angle of cantant or lap.
\(θ=(180°+2α)\frac{π}{180}rad\)
\(=3.2 rad\)		 Comments Active
96 Which of the following is the CORRECT methods for the conversion of spring controlled governor from unstable to stable? Increasing the ball weight Decreasing the spring stiffness Decreasing the ball weight Increasing the spring stiffness d A spring controlled governor can be made stable by increasing the spring stiffness. A governor is said to be stable when for every speed within the working range there is a definite configuration i.e. there is only one radius of rotation of the governor balls at which the governor is in equilibrium. Comments Active
97 Which of the following is TRUE for four bar mechanism? All sliding pairs One is sliding pair and other is turning pair All turning pairs None of these c A kinematic chain is a combination of four or more kinematic pairs, such that the relative motion between the links or elements is completely constrained. The simplest and the basic kinematic chain is a four-bar chain or quadric cycle chain.
It consists of four links, each of them forms a turning pair at A, B, C and D. The four links may be of different lengths.		 Comments Active
98 How many degrees of freedom does the below mechanism have?
 0 1 2 3 c L = 5
j =5
h = 0
f = 3 (L – 1) – 2 j – h
= 3 (5 – 1) – 2 5 – 0 \(×\)
= 12 – 10
F = 2		 Comments Active
99 What are the numbers of binary and ternary links in the following kinematic chain?
 3 binary and 4 ternary joints 3 binary and 3 ternary joints 3 binary and 2 ternary joints 4 binary and 2 ternary joints All options are wrong (Cancelled by ssc) No. of links = 6
No. of binary joints (binary) = 7
No. of ternary joints = 0		 Comments Active
100 Choose the option which does NOT belong to the category of simple machine Spring Screw Wedge Pulley a A simple machine is a device that simply transforms the direction or magnitude of a force, but a large number of more complex machines exist.
Examples include Levers, Screw Jack, Wheel and axle, Pulleys, Wedge, Inclined plane, etc.
Spring stores and releases energy. it neither's changed direction or magnitude of the force. To qualify as a simple machine, a device must exchange the magnitude of a Force.		 Comments Active