Mechanical Engineering

Which of the following is a mesomorphous material ?

For two governors A and B, the lift of sleeve of governor A is more than that of governor B, fora given fractional change in speed. It indicates that

To make a worm drive reversible, it is necessary to increase  

The mass of each ball of a Proell Governor is 3 kg and the weight on the sleeve is 20 kg. Each arm is 220 mm long and the pivots of upper and lower arms are 20 mm from the axis. For the mid position of the sleeve, the extension links of the lower arms are vertical, the height of the governor is 180 mm, the speed is 150 rpm and the radius of path of rotation of the masses is 147 mm. Determine the lengths of the extension link (in mm).

When a component is subjected to axial stress the normal stress σ_n is maximum, if cos θ is _______ . (σ_n=σ_xCos²θ)

1. maximum
2. minimum
3. always one
4. always zero

The material used for brake lining should have __________ coefficient of friction.

The above figure shows a cam with a circular profile, rotating with a uniform angular velocity of ω rad/s.
What is the nature of displacement of the follower?

Consider the following two processes:

a. A heat source at 1200 K loses 2500 kJ of heat to sink at 800 K

b. A heat source at 800 K loses 2000 kJ of heat to sink at 500 K

Which of the following statements is TRUE?

When a shear stress is applied to a substance, it is found to resist it by static deformation, the  substance is 

The Euler's equation for the motion of liquids is based upon the assumption that

 The top of the piston in two-stroke engine is

Which of the following is boiler mounting ?

The maximum fluctuation of speed is the

If a bearing is designated by the number 305, it means that the bearing is of

A spherical pressure vessel is to be designed tohold 40 MPa pressure and Diameter should be200 mm. If max stress can be 200 MPa find thethickness required.

The centre of gravity of a right circular solid cone is at a distance of __________ from its base, measured along the vertical axis.(where h = Height of a right circular solid cone.)

In a 3 ton capacity water cooler, water enters at 30ºC and leaves at 15ºC steadily. What is the water flow rate per hour ?

The domestic refrigerator has.a refrigeration load of the order of

Determine the couple moment acting on the beam shown.

The given diagram shows an isometric cooling process 1–2 of a pure substance. The ordinate and abscissa are respectively

The concept of continuum in fluid flow assumes that the characteristics length of the flow is 

Which of the following is not the desirable property of a good fuel?

The moment of inertia of a solid cylinder of mass m, radius r and length l about the longitudinal axis or polar axis is

A circular shaft subjected to twisting moment results in maximum shear stress of 60 MPa. Then the maximum compressive stress in the material is

In forced circulation boilers, about 90% of water is recirculated without evaporation. The circulation ratio is

Consider a two dimensional state of stress given for an element as shown in the diagram given below: What are the coordinates of the centre of Mohr's circle

Which one of the following is true in respect of production control for continuous or assembly line production? 

When the molten metal is poured in a mould, it may pass through the following items in sequence

In which of the following welding techniques in vacuum environment required

The c.g. of a link in any mechanism would experience

Magnesium crystallizes in HCP structure. If the lattice constant is 0.32 nm, the nearest neighbour distance in magnesium is

What is the deformation or dynamic factor if sum of errors on meshing teeth of steel pinion and gear is 32 x 10^-3 mm?

Discharge of a centrifugal pump is

∇ × ∇ × P, where P is a vector, is equal to  

A jet of oil with relative density 0.7 strikes normally a plate with a velocity of 10 m/s. The jet has an area of 0.03 m^2. The force exerted on the plate by the jet is

The prime circle of a cam is

The essential condition for the transfer of heat from one body to another is.

The intake charge in a diesel engine consists of

The controlling force curves for a spring-controlled governor are shown in the above figure. Which curve represents a stable governor?

The working surface above the pitch surface of the gear tooth is termed as

The amount of water evaporated in kg per kg of fuel burnt is called

The bolts in a rigid flanged coupling connecting two shafts transmitting power are subjected to

Alcohol is used in manometers because

There is no work transfer involved in this process

Mass is best given by _______

नीचे दिए गये प्रत्येक प्रश्न में कुछ कथन और उसके बाद कुछ निष्कर्ष दिए गये हैं। आपको दिए गये कथनों को सत्य मानना है, भले ही वे ज्ञात तथ्यों से अलग प्रतीत होते हो, सभी निष्कर्षो को पढ़िए और फिर निर्णय कीजिये कि दिए गये निष्कर्षो में से कौन-सा/कौन-से निष्कर्ष ज्ञात तथ्यों को नजरअंदाज करने पर कथनों का तार्किक रूप से अनुसरण करता है/करते हैं।

I. कुछ कलम काले हैं।

II. कुछ कलम नीले हैं।

III. कोई काला लाल नहीं हैं।

I. कोई कलम लाल नहीं हैं।

II. कुछ नीले काले हैं।

III. कुछ काले कलम हैं।

Assertion (A): There is good grain refinement in hot working.
Reason (R): In hot working physical properties are generally improved. 

A thin cylinder contains fluid at a pressure of 500 N/m², the internal diameter of the shell is 0.6 m and the tensile stress in the material is to be limited to 9000 N/m². The shell must have a minimum wall thickness of nearly

If two blocks of equal mass are attached to the two ends of a light string and one of the blocks is placed over a smooth horizontal plane while the other is hung freely after passing over a smooth pulley, then the two blocks will have some motion.

   A system comprising a single phase is called a

A safety valve usually employed with stationary boilers is

A gas turbine works on which one of the following cycles?

Match List I (Items in joints) with List II (Type of failure) and select the correct answer using the codes given below the Lists:   

Codes A B C D

A gear set has a pinion with 20 teeth and a gear with 40 teeth. The pinion runs at 30 rev/s and transmits a power of 20 kW. The teeth are on the 20c full-depth system and have a module of 5 mm. The length of the line of action is 19 mm.

For a given value of TH (Source temperature) for a reversed Carnot cycle, the variation of TL(Sink temperature) for different values of COP is represented by which one of the following graphs ?

When the engines are built to withstand the same thermal and mechanical stresses

Consider the following operations involved in forging a hexagonal bolt from a round bar stock, whose diameter is equal to the bolt diameter:
1. Flattening 2. Upsetting 3. Swaging 4. Cambering

Q.

The correct sequence of these operations is

Newton's law of viscosity is a relationship between

For an engine which cannot start when loaded the type of clutch that should be used is

The shearing area of a key of length 'L', breadth 'b' and depth 'h' is equal to   

Consider the following stress-strain diagram and match the following:
List - I

List - II
1. Hard rubber
2. Soft rubber
3. Structural steel
4. Aluminium alloy

The flight Mach number of an aircraft flying at an altitude where the temperature is -48°C is 0.7. The speed of the aircraft is (Take γ = 1.4, 77= 287 J/kgK)

Match List-1 (Materia!) with List-ll (Poisson’s Ratio)

The three major types of forecasts used by business organizations are

Falling drops of water become spheres due to the property of

If velocity of slider is 4m/s and The angular velocity of the link where the slider is sliding is 5 rad/s the coriolis acceleration is

Which one of the following welding processes consists of minimum heat affected zone (HAZ)?   

For a cotter, the ratio of thickness to width is

The B.M.D. for a cantilever beam due to its selfweight is

According to law of gearing

In order to withstand resistance to wear, the best profile of gear is

A body is subjected to a pure tensile stress of 100 units. What is the maximum shear produced in the body at some oblique plane due to the above ?

The factor of safety for steel and for steady load is

Which of the following parameters is/are false for steel?