question_answer 1)
The voltage-current characteristics of a DC generator for arc welding is a straight line between an open circuit voltage of 80 V and short-circuit current of 300 A. The generator settings for maximum arc power will be:
A)
80 V and 150 A done
clear
B)
40 V and 300 A done
clear
C)
40 V and 150 V done
clear
D)
V and 300 A done
clear
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question_answer 2)
Which one of the following features improves the fatigue strength of a metallic material?
A)
Increasing the temperature done
clear
B)
Scratching the surface done
clear
C)
Overstressing done
clear
D)
Under stressing done
clear
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question_answer 3)
Which one of the following pairs is correctly matched?
A)
Beauchamp tower first experiments on journal bearings done
clear
B)
Osborne Reynolds antifriction bearings done
clear
C)
Sommerfeld number pivot and collar bearings done
clear
D)
Ball bearings hydrodynamic lubrication done
clear
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question_answer 4)
Which of the following joining processes are best suited for manufacturing pipes to carry gas products?
1. Rivetting 2. Welding 3. Bolts and nuts Select the correct answer using the codes given below:
Codes:
A)
1 and 2 done
clear
B)
1 and 3 done
clear
C)
2 alone done
clear
D)
1, 2 and 3 done
clear
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question_answer 5)
The correct sequence of the given materials in ascending order of their Weldability is:
A)
MS, copper, cast iron, aluminium done
clear
B)
Cast iron, MS, aluminium copper done
clear
C)
Copper, cast iron, MS, aluminium done
clear
D)
Aluminium, copper, cast iron, MS done
clear
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question_answer 6)
A screw thread specified by \[M\,\,20\times 25\,\,C\] as per BIS thread system means:
A)
Metric thread of 20 mm nominal diameter and 2.5 mm pitch having coarse tolerance done
clear
B)
Metric thread of 20 mm root diameter and 2-5 mm pitch having coarse tolerance done
clear
C)
Metric thread of fine class having 20 mm root diameter and 2.5 mm pitch done
clear
D)
Metric thread of 20 mm shank diameter and 25 mm thread depth with coarse tolerance. done
clear
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question_answer 7)
Which one of the following statements is correct?
A)
No Flux is used in gas welding of mild steel done
clear
B)
Borax is the commonly used flux coating on welding electrodes done
clear
C)
Laser beam welding employs a vacuum chamber and thus avoids use of a shielding method done
clear
D)
AC can be used for GTAW process done
clear
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question_answer 8)
Which one of the following statements with regard to belt drives is not correct?
A)
Increase in the angle of wrap of the belt enables more power transmission done
clear
B)
Maximum power is transmitted when the centrifugal tension is three times the tight side tension done
clear
C)
Wide and thin belt is preferable for better life than a thick and narrow one done
clear
D)
Crown is provided on the pulley to make the belt run centrally on the pulley done
clear
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question_answer 9)
Angle of twist of a shaft of diameter d? is inversely proportional to:
A)
d done
clear
B)
\[{{d}^{2}}\] done
clear
C)
\[{{d}^{3}}\] done
clear
D)
\[{{d}^{4}}\] done
clear
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question_answer 10)
Which one of the following sets of parameters should be monitored for determining safe operation of journal bearing?
A)
Oil pressure, bearing metal temperature and bearing vibration done
clear
B)
Bearing vibration, oil pressure and speed or shaft done
clear
C)
Bearing metal temperature oil pressure done
clear
D)
Oil pressure and bearing vibration. done
clear
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question_answer 11)
The performance of a hydrodynamic journal bearing is a function of:
A)
Reynolds number done
clear
B)
Sommerfield number done
clear
C)
Speed done
clear
D)
Bearing modulus done
clear
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question_answer 12)
Match List-I (Nature of Failure) with List-II (Nature of Member) and select the correct answer using the codes given below the lists:
List-I (Nature of failure) List-II (Nature of Member) A. Structural member fails in axial compression 1. Knuckle Joint B. A member fail along a \[45{}^\circ \] helical plane subjected to torsion 2. Long column C. A structural member bends and collapses under axial compression load 3. Strut D. A member fails in double shear for a joint 4. Cast iron round bar subjected to torsion
Codes:
A)
A\[\to \]3, B\[\to \]1, C\[\to \]2, D\[\to \]4 done
clear
B)
A\[\to \]2, B\[\to \]4, C\[\to \]3, D\[\to \]1 done
clear
C)
A\[\to \]3, B\[\to \]4, C\[\to \]2, D\[\to \]1 done
clear
D)
A\[\to \]2, B\[\to \]1, C\[\to \]3, D\[\to \]4 done
clear
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question_answer 13)
Which one of the following correctly relates the life of a roller bearing in millions of revolutions (L) the load P and the basic dynamic load rating for 1 million revolutions C?
A)
\[L={{(C/P)}^{3}}\] done
clear
B)
\[L={{(C/P)}^{10/3}}\] done
clear
C)
\[L={{(P/C\,)}^{3}}\] done
clear
D)
\[L={{(C/P)}^{1/3}}\] done
clear
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question_answer 14)
Match List-I with List-II and select the correct answer using the codes given below the lists:
List-I (Type of Thread) List-II (Use) A. Square thread 1. Used in vice B. Acme thread 2. Used in lead screw C. Buttress thread 3. Used in screw jack D. Trapezoidal thread 4. Used in power transmission devices in machine tool
Codes:
A)
A\[\to \]2, B\[\to \]3, C\[\to \]4, D\[\to \]1 done
clear
B)
A\[\to \]2, B\[\to \]3, C\[\to \]1, D\[\to \]4 done
clear
C)
A\[\to \]3, B\[\to \]2, C\[\to \]1, D\[\to \]4 done
clear
D)
A\[\to \]3, B\[\to \]2, C\[\to \]4, D\[\to \]1 done
clear
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question_answer 15)
The number of slots in a 25 mm castle nut are:
A)
2 done
clear
B)
4 done
clear
C)
6 done
clear
D)
8 done
clear
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question_answer 16)
Which key is preferred for the condition where a large amount of impact torque is to be transmitted in both direction of rotation:
A)
Woodruff key done
clear
B)
Feather key done
clear
C)
Gib-head key done
clear
D)
Tangent key done
clear
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question_answer 17)
Which of the following is true about following specifications: Hex Bolt M 16 NL-IS: 1363:
A)
16 eye bolts used on electric motors done
clear
B)
A stress relieved blot for connecting rod done
clear
C)
A bolt with a nut done
clear
D)
A bolt with a nut and a lock nut done
clear
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question_answer 18)
Which bearing is preferred for oscillating conditions?
A)
Double row roller hearing done
clear
B)
Angular contact single row ball bearing done
clear
C)
Taper roller bearing done
clear
D)
Needle roller hearing done
clear
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question_answer 19)
Ball bearings are provided with a cage:
A)
To reduce friction done
clear
B)
To maintain the halls at a fixed distance apart done
clear
C)
To prevent the lubricant from flowing out done
clear
D)
To facilitate slipping of balls. done
clear
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question_answer 20)
Thick steel plate cut with oxygen normally shows signs of cracking. This tendency for cracking can be minimized by:
A)
Slow speed cutting done
clear
B)
Cutting in two or more stages done
clear
C)
Preheating the plate done
clear
D)
Using oxy-acetylene flame done
clear
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question_answer 21)
Jewel bearings are used in:
A)
Contaminated atmosphere done
clear
B)
low-torque applications done
clear
C)
Fully immersed in water condition done
clear
D)
High speed shafts done
clear
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question_answer 22)
Match List-I with List-II and select the correct answer using the codes given below the lists:
List-I (Type of joint) List-II (Mode of joining members) A. Cotter joint 1. Connects two rods or bars permitting small amount of flexibility B. Knuckle joint 2. Rigidly connects two members C. Turn buckle 3. Connects two rods having threaded ends D. Riveted joint 4. Permanent fluid-tight joint between two plates. 5. Connects two shafts and transmits torque
Codes:
A)
A\[\to \]5, B\[\to \]1, C\[\to \]3, D\[\to \]2 done
clear
B)
A\[\to \]2, B\[\to \]1, C\[\to \]3, D\[\to \]4 done
clear
C)
A\[\to \]5, B\[\to \]3, C\[\to \]2, D\[\to \]4 done
clear
D)
A\[\to \]2, B\[\to \]3, C\[\to \]1, D\[\to \]4 done
clear
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question_answer 23)
The most efficient riveted joint possible is one which would be as strong in tension, shear and bearing as the original plates to be joined. But this can never be achieved because:
A)
Rivets cannot be made with the same material done
clear
B)
Rivets are weak in compression done
clear
C)
There should be at least one hole in the plate reducing its strength done
clear
D)
Clearance is present between the plate and the rivet done
clear
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question_answer 24)
Which of the following stresses are associated with the tightening of a nut on a stud?
A)
Tensile stresses due to stretching of stud. done
clear
B)
Bending stresses of stud. done
clear
C)
Transverse shear stresses across threads. done
clear
D)
Torsional shear stresses in threads due to frictional resistance done
clear
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question_answer 25)
The frictional torque for square thread at mean radius while raising load is given by \[(W=load,\,{{R}_{0}}\,=\,\]Mean Radius,\[\phi =\]Angle of friction, \[\alpha \,=\,\]Helix angle):
A)
\[W{{R}_{0}}\tan (\phi -\alpha )\] done
clear
B)
\[W{{R}_{0}}\tan (\phi +\alpha )\] done
clear
C)
\[W{{R}_{0}}\tan \alpha \] done
clear
D)
\[W{{R}_{0}}\tan \phi \] done
clear
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question_answer 26)
In a belt drive, if the pulley diameter is doubled keeping the tension and belt width constant, then it will be necessary to:
A)
Increase the key length done
clear
B)
Increase the key depth done
clear
C)
Increase the key width done
clear
D)
Decrease the key length done
clear
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question_answer 27)
Consider the following statements:
1. Grinding 2. Coating 3. Hammer peening
For improving the fatigue strength of steel. Of the above statements:
A)
1 and 2 are correct done
clear
B)
2 and 3 are correct done
clear
C)
1 and 3 are correct done
clear
D)
1, 2 and 3 are correct. done
clear
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question_answer 28)
The following data refers to an open belt drive:
Pulley A Pulley B Purpose?. Driving Driving Diameter?. 450 mm 750 mm Angle of contact?. \[{{\theta }_{A}}\,=\,150\] \[{{\theta }_{B}}\,=\,210{}^\circ \] Coefficient of friction between belt and pulley \[{{f}_{A}}\,=\,0.36\] \[{{f}_{B}}\,=\,0.22\]
The ratio of tensions may be calculated using the Relation \[({{T}_{1}}/{{T}_{2}})\,=\]exp (z) where z is:
A)
\[{{f}_{A}}{{\theta }_{A}}\] done
clear
B)
\[{{f}_{B}}{{\theta }_{B}}\] done
clear
C)
\[({{f}_{A}}+{{f}_{B}})\,({{\theta }_{A}}+{{\theta }_{B}})/4\] done
clear
D)
\[({{f}_{A}}{{\theta }_{A}}+{{f}_{B}}{{\theta }_{B}})/2\] done
clear
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question_answer 29)
In a multiple V-belt drive, when angle belt is damaged, it is preferable to change the complete set to:
A)
Reduce vibration done
clear
B)
Reduce slip done
clear
C)
Ensure uniform loading done
clear
D)
Ensure proper alignment done
clear
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question_answer 30)
Design of shafts made of brittle material is based on:
A)
Guest's theory done
clear
B)
Rankine's theory done
clear
C)
St. Venant's theory done
clear
D)
Von-Mises theory. done
clear
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question_answer 31)
A motor car has wheel base of 280 cm and the pivot distance of front stub axles is 140 cm. When the outer wheel has turned through 30, the angle of turn of the inner front wheel for correct steering will be:
A)
\[60{}^\circ \] done
clear
B)
\[{{\cot }^{-1}}2.23\] done
clear
C)
\[{{\cot }^{-1}}1.232\] done
clear
D)
\[30{}^\circ \] done
clear
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question_answer 32)
Match List-I with List-II and select answer using the codes given below the Lists:
List-I (Types of joints) List-II (An element of the joint) A. Riveted joint 1. Pin B. Welded joint 2. Strap C. Bolted joint 3. Lock washer D. Knuckle joint 4. Fillet
Codes:
A)
A\[\to \]4, B\[\to \]3, C\[\to \]2, D\[\to \]1 done
clear
B)
A\[\to \]2, B\[\to \]3, C\[\to \]4, D\[\to \]1 done
clear
C)
A\[\to \]2, B\[\to \]4, C\[\to \]3, D\[\to \]1 done
clear
D)
A\[\to \]2, B\[\to \]4, C\[\to \]1, D\[\to \]3 done
clear
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question_answer 33)
Consider the following statements regarding power screws:
1. The efficiency of a self-locking screw cannot be more than 50% 2. If the friction angle is less than the helix angle of the screw, then the efficiency will be more than 50% 3. The efficiency of ACME (trapezoidal) thread is less than that of square thread.
Of these statements:
A)
1, 2 and 3-are correct done
clear
B)
2 and 3 are correct done
clear
C)
1 and 3 are correct done
clear
D)
1 and 2 are correct done
clear
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question_answer 34)
Electron beam welding can be carried out in:
A)
Open air done
clear
B)
A shielding gas environment done
clear
C)
A pressurized inert gas chamber done
clear
D)
Vacuum done
clear
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question_answer 35)
Given that \[p\,=\] chain pitch C = Centre distance N, n = number of teeth on large and small sprocket respectively, The length of chain in terms of pitches can be approximated by:
A)
\[\frac{2C}{P}\] done
clear
B)
\[\frac{2C}{P}+(N+n)/2\] done
clear
C)
\[\frac{2C}{P}+\left[ \frac{N+n}{2\pi } \right]\frac{p}{C}\] done
clear
D)
\[\frac{2C}{P}+\frac{N+n}{2p}{{\left[ \frac{N-n}{2p} \right]}^{2}}\,\frac{p}{C}\] done
clear
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question_answer 36)
When compared to a rod of the same diameter and material, a wire rope:
A)
Is less flexible done
clear
B)
Has a much smaller load carrying capacity done
clear
C)
Does not provide much warning before failure done
clear
D)
Provides much greater time for remedial action before failure done
clear
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question_answer 37)
A shafts subjected to fluctuating loads for which the normal torque (T) and bending moment (M) are 1000 N-m add 500 N-m respectively. If the combined shock and fatigue factor for bending is 1.5 and combined shock and fatigue factor for torsion is 2, then the equivalent twisting moment for the shaft is:
A)
2000-N-m done
clear
B)
2050 N-m done
clear
C)
2100 N-m done
clear
D)
2136 N-m done
clear
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question_answer 38)
The lead angle of a worm is \[22.5{}^\circ .\] Its helix angle will be:
A)
\[22.5{}^\circ \] done
clear
B)
\[45{}^\circ \] done
clear
C)
\[67.5{}^\circ \] done
clear
D)
\[90{}^\circ \] done
clear
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question_answer 39)
Consider the following statements about anti- friction bearings:
1. They have low starting and low running friction at moderate speeds 2. They have high resistance to shock loading. 3. They can carry both radial and thrust loads. 4. Their initial cost is high. 5. They can accommodated some amount of misalignment of shaft.
Of these statements:
A)
1, 2, 3 and 4 done
clear
B)
1, 3 and 4 are correct done
clear
C)
1, 4 and 5 are correct done
clear
D)
1, 2, 3 and 5 are correct done
clear
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question_answer 40)
The load cup of a screw jack is made separate from the head of the spindle to:
A)
Enhance the load carrying capacity of the jack done
clear
B)
Reduce the effort needed for lifting the working load done
clear
C)
Reduce the value of frictional torque to be countered for lifting the load done
clear
D)
Prevent the rotation of load being lifted done
clear
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question_answer 41)
A bolt of uniform strength can be developed by:
A)
Keeping the core diameter of threads equal to the diameter of unthreaded portion of the bolt. done
clear
B)
Keeping the core diameter smaller than the diameter of the unthreaded portion. done
clear
C)
Keeping the nominal diameter of threads equal the diameter of unthreaded portion of the bolt. done
clear
D)
One end fixed and the other end free. done
clear
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question_answer 42)
Which designing a screw is a screw jack against buckling failure, the end conditions for the screw are taken as:
A)
Both the ends fixed done
clear
B)
Both the ends hinged done
clear
C)
One end fixed and other end hinged done
clear
D)
One end fixed and there end free done
clear
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question_answer 43)
Match List-I with List-II and select the correct answer using the codes given below the list:
List-I (Different types of detachable joints) List-II (Specific use of these detachable joints) A. Cotter joint 1. Tie rod of a wall crane B. Knuckle joint 2. Suspension bridges C. Suspension link joint 3. Diagonal stays in boiler D. Turn buckle (adjustable joint) 4. Cross-head a steam engine
Codes:
A)
A\[\to \]4, B\[\to \]2, C\[\to \]3, D\[\to \]1 done
clear
B)
A\[\to \]4, B\[\to \]3, C\[\to \]2, D\[\to \]1 done
clear
C)
A\[\to \]3, B\[\to \]2, C\[\to \]1, D\[\to \]4 done
clear
D)
A\[\to \]2, B\[\to \]1, C\[\to \]4, D\[\to \]3 done
clear
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question_answer 44)
A spur gear transmitting power is connected to the shaft with a key of rectangular section. The type (s) of stresses developed in the key is/are:
A)
Shear stress alone done
clear
B)
Hearing stress alone done
clear
C)
Both shear and bearing stresses done
clear
D)
Shearing, bearing and bending stresses. done
clear
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question_answer 45)
The permissible stress in a filled weld is 100 N/mm. The fillet weld has equal leg lengths of 15 mm each. The allowable shearing load on weldment per cm length of the weld is:
A)
225 kN done
clear
B)
15.0 kN done
clear
C)
10.6 kN done
clear
D)
7.5 kN done
clear
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question_answer 46)
Sources of power loss in a chain drive are given below:
1. Friction between chain and sprocket teeth. 2. Overcoming the chain stiffness. 3. Overcoming the friction in shaft bearing. 4. Frictional resistance of the motion of the chain in air or lubricant.
The correct sequence of descending order of power loss due to these sources is:
A)
1, 2, 3, 4 done
clear
B)
1, 2, 4, 3 done
clear
C)
2, 1, 3, 4 done
clear
D)
2, 1, 4, 3 done
clear
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question_answer 47)
Consider the following design considerations:
1. Tensile failure 2. Creep failure 3. Bearing failure 4. Shearing failure 5. Bending failure
The design of the pin of a rocker arm of an I.C. engine is based on:
A)
1, 2 and 4 done
clear
B)
1, 3 and 4 done
clear
C)
2, 3 and 5 done
clear
D)
3, 4 and 5 done
clear
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question_answer 48)
Which one of the following loadings is considered for design of axles?
A)
Bending moment only done
clear
B)
Twisting moment only done
clear
C)
Combined bending moment and torsion done
clear
D)
Combined action of bending moment, twisting moment and axial thrust. done
clear
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question_answer 49)
Removal of metal particles from the raceway of a roiling contact bearing is a kind of failure of bearing known as:
A)
Pitting done
clear
B)
Wearing done
clear
C)
Spilling done
clear
D)
Scuffing done
clear
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question_answer 50)
The design calculations of members subject to fluctuating loads with the same factor of safety yield the most conservative estimates when using:
A)
Gerber relation done
clear
B)
Soderberg relation done
clear
C)
Goodman relation done
clear
D)
None of the above done
clear
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question_answer 51)
Match List-I with List-II and select the correct answer using the codes given below the lists:
List-I List-II A. Crank shaft 1. Supports the revolving part and transmits torque. B. Wire shaft 2. Transmits motion between shafts where is not possible to effect rigid coupling between them. C. Axle 3. Converts linear motion into rotary motion. D. Plain shaft 4. Supports only the revolving parts.
Codes:
A)
A\[\to \]3, B\[\to \]2, C\[\to \]1, D\[\to \]4 done
clear
B)
A\[\to \]4, B\[\to \]2, C\[\to \]3, D\[\to \]1 done
clear
C)
A\[\to \]3, B\[\to \]2, C\[\to \]4, D\[\to \]1 done
clear
D)
A\[\to \]1, B\[\to \]4, C\[\to \]2, D\[\to \]3 done
clear
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question_answer 52)
Match List-I with List-II and select the correct answer using the codes given below the lists:
List-I (Terminology) List-II (Relevant term) A. Interference 1. Arc of approach, arc of recess, circular pitch. B. Dynamic load on tooth 2. Lewis equation. C. Static load 3. Minimum number of teeth on pinion. D. Contact ratio 4. Inaccuracies in tooth profile
Codes:
A)
A\[\to \]3, B\[\to \]4, C\[\to \]1, D\[\to \]2 done
clear
B)
A\[\to \]1, B\[\to \]2, C\[\to \]3, D\[\to \]4 done
clear
C)
A\[\to \]4, B\[\to \]3, C\[\to \]2, D\[\to \]1 done
clear
D)
A\[\to \]3, B\[\to \]4, C\[\to \]2, D\[\to \]1 done
clear
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question_answer 53)
Match List-I with List-II and select the correct answer using the codes given below the lists:
List-I (Name) List-II (Type) A. Oldham coupling 1. Joins collinear shafts and is rigid type. B. Flange coupling 2. Joins non-collinear shafts and is adjustable. C. Universal coupling 3. Joins collinear shafts and engages and disengages them during motion. D. Friction coupling 4. Compensates peripheral shafts, longitudinal and angular shifts of shafts.
Codes:
A)
A\[\to \]2, B\[\to \]1, C\[\to \]4, D\[\to \]3 done
clear
B)
A\[\to \]3, B\[\to \]2, C\[\to \]1, D\[\to \]4 done
clear
C)
A\[\to \]1, B\[\to \]4, C\[\to \]2, D\[\to \]3 done
clear
D)
A\[\to \]2, B\[\to \]3, C\[\to \]1, D\[\to \]4 done
clear
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question_answer 54)
Match List-I with List-II and select the correct answer using the codes given below the lists:
List-I (Requirement) List-II (Type) A. High temperature service. 1. Teflon bearing B. High load 2. Carbon bearing C. No lubrication 3. Hydrodynamic bearing D. Bushings 4. Sleeve bearing
Codes:
A)
A\[\to \]1, B\[\to \]2, C\[\to \]3, D\[\to \]4 done
clear
B)
A\[\to \]4, B\[\to \]1, C\[\to \]2, D\[\to \]3 done
clear
C)
A\[\to \]2, B\[\to \]1, C\[\to \]3, D\[\to \]4 done
clear
D)
A\[\to \]2, B\[\to \]3, C\[\to \]1, D\[\to \]4 done
clear
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question_answer 55)
In the calculation of induced shear stress in helical springs, the Wahl's correction factor is used to take care of:
A)
Combined effect of transverse shear stress and bending stress in the wire. done
clear
B)
Combined effect of bending stress and curvature of the wire. done
clear
C)
Combined effect of transverse shear stress and curvature of the wire. done
clear
D)
Combined effect of torsional shear stress an transverse shear stress in the wire done
clear
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question_answer 56)
Two rigid plates are clamped by means of bolt and nut with an initial force N. After tightening, separating force P (P<N) is applied to the Lower plate, which in turn ads on nut. The tension in the bolt after this is:
A)
(N+P) done
clear
B)
\[\left( N-P \right)\] done
clear
C)
P done
clear
D)
N done
clear
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question_answer 57)
To ensure self-locking in a screw jack it is essential that helix angle is:
A)
Larger than friction angle done
clear
B)
Smaller than friction angle done
clear
C)
Equal to friction angle done
clear
D)
Such as to give maximum efficiency in lifting done
clear
View Solution play_arrow
question_answer 58)
A double fillet welded joint with parallel fillet weld of length L and leg B is subjected to a tensile force P. Assuming uniform stress distribution, the shear stress in distribution, the shear stress the weld is given by:
A)
\[\frac{\sqrt{2.}\,P}{BL}\] done
clear
B)
\[{{\sigma }_{1}}=\frac{P}{2hl}\] done
clear
C)
\[\frac{P}{\sqrt{2.}B.L}\] done
clear
D)
\[\frac{2P}{B.L}\] done
clear
View Solution play_arrow
question_answer 59)
In flat belt drive, if the slip between the driver and the belt is 1%, that between belt and follower is 3% and driver and follower pulley diameters are equal, then the velocity ratio of the drive will be:
A)
0.99 done
clear
B)
0.98 done
clear
C)
0 0.97 done
clear
D)
0.96 done
clear
View Solution play_arrow
question_answer 60)
Effective stress in wire ropes during normal working is equal to the stress due to:
A)
Axial load plus stress due to bending done
clear
B)
acceleration/retardation of masses plus stress due to bending done
clear
C)
Axial load plus stress due to acceleration/ retardation done
clear
D)
bending plus stress due to acceleration/retardation done
clear
View Solution play_arrow
question_answer 61)
A transmission shaft subjected to bending loads must be designed on the basis of:
A)
Maximum normal stress theory done
clear
B)
Maximum shear stress theory done
clear
C)
Maximum normal stress and maximum shear stress theories done
clear
D)
Fatigue strength done
clear
View Solution play_arrow
question_answer 62)
Consider the following statements:
The form factor of a spur gear tooth depends upon the 1. Number of teeth 2. Pressure angle. 3. Addendum modification. 4. Circular pitch.
Of these statements:
A)
1 and 3 are correct done
clear
B)
1 and 4 are correct done
clear
C)
1, 2 and 3 are correct done
clear
D)
1 and 4 are correct done
clear
View Solution play_arrow
question_answer 63)
When belt drive is transmitting maximum power:
A)
Effective tension is equal to centrifugal tension done
clear
B)
Effective tension is half of centrifugal tension done
clear
C)
Driving tension on slack side is equal to the centrifugal tension done
clear
D)
Driving tension on tight side is twice the centrifugal tension done
clear
View Solution play_arrow
question_answer 64)
Tapered roller bearing can take:
A)
Radial load only done
clear
B)
Axial load only done
clear
C)
Both radial and axial loads and the ratio of these being less than unity done
clear
D)
Both radial and axial loads and the ratio of these being greater than unity done
clear
View Solution play_arrow
question_answer 65)
In bearing characteristic number in a hydrodynamic bearing depends on:
A)
It is closer to real life situation done
clear
B)
It leads to a safer design done
clear
C)
It leads to cost effective design done
clear
D)
No other assumption is possible done
clear
View Solution play_arrow
question_answer 66)
The bearing characteristic number in a hydrodynamic bearing depends on:
A)
Length, width and load done
clear
B)
Length, width and speed done
clear
C)
Viscosity, speed and load done
clear
D)
Viscosity, speed and bearing pressure done
clear
View Solution play_arrow
question_answer 67)
Which one of the following welding processes uses non-consumable electrodes?
A)
TIG welding done
clear
B)
MIG welding done
clear
C)
Manual arc welding done
clear
D)
Submerged arc welding done
clear
View Solution play_arrow
question_answer 68)
Match List-I with List-II and Select the correct answer using the codes given below the Lists:
List-I (Filler) List-II (Joining process) A. Cu, Zn, Ag, alloy 1. Braze welding B. Cu, Sn alloy 2. Brazing C. Pb, Sb alloy 3. Soldering D. Iron oxide and aluminium powder 4. TIG welding of aluminium.
Codes:
A)
A\[\to \]1, B\[\to \]1, C\[\to \]1, D\[\to \]3 done
clear
B)
A\[\to \]4, B\[\to \]2, C\[\to \]3, D\[\to \]4 done
clear
C)
A\[\to \]2, B\[\to \]1, C\[\to \]2, D\[\to \]3 done
clear
D)
A\[\to \]2, B\[\to \]4, C\[\to \]2, D\[\to \]3 done
clear
View Solution play_arrow
question_answer 69)
The maximum efficiency of a self-locking screw is:
A)
50% done
clear
B)
70% done
clear
C)
75% done
clear
D)
80% done
clear
View Solution play_arrow
question_answer 70)
Match List-I (Type of keys) with List-II (Characteristic) and select the correct answer using the codes given below the Lists:
List-I List-II A. Woodruff key 1. Loose fitting, light duty B. Kennedy key 2. Heavy duty C. Feather key 3. Self-aligning D. Flat key 4. Normal industrial use
Codes:
A)
A\[\to \]2, B\[\to \]3, C\[\to \]1, D\[\to \]4 done
clear
B)
A\[\to \]3, B\[\to \]2, C\[\to \]1, D\[\to \]4 done
clear
C)
A\[\to \]2, B\[\to \]3, C\[\to \]4, D\[\to \]1 done
clear
D)
A\[\to \]3, B\[\to \]2, C\[\to \]4, D\[\to \]1 done
clear
View Solution play_arrow
question_answer 71)
Consider the following statements:
MIG welding process uses 1. Consumable electrode 2. Non-consumable electrode 3. D. C power supply 4. A. C power supply.
Of these statements:
A)
2 and 4 are correct done
clear
B)
2 and 3 arc correct done
clear
C)
1 and 4 are correct done
clear
D)
1 and 3 are correct done
clear
View Solution play_arrow
question_answer 72)
In the case of a vertical belt pulley drive with \[{{T}_{C}}\] as centrifugal tension and \[{{T}_{0}}\] as the initial tension, the belt would tend to hang clear of the lower pulley when:
A)
\[{{T}_{c}}\]<\[{{T}_{0}}\] done
clear
B)
\[{{T}_{c}}\,=\,{{T}_{0}}/3\] done
clear
C)
\[{{T}_{c}}\]>\[{{T}_{0}}\] done
clear
D)
\[{{T}_{c}}\,=\,{{T}_{0}}/2\] done
clear
View Solution play_arrow
question_answer 73)
Given that \[{{T}_{1}}\] and \[{{T}_{2}}\] are the tensions on the tight and slack of the belt respectively, the initial tension of the belt taking centrifugal tension \[{{T}_{c}}\] is equal to:
A)
\[\frac{{{T}_{1}}+{{T}_{2}}+{{T}_{c}}}{3}\] done
clear
B)
\[\frac{{{T}_{1}}+{{T}_{2}}+2{{T}_{c}}}{2}\] done
clear
C)
\[\frac{{{T}_{1}}+{{T}_{2}}+3{{T}_{c}}}{2}\] done
clear
D)
\[\frac{{{T}_{1}}+{{T}_{2}}+4{{T}_{c}}}{3}\] done
clear
View Solution play_arrow
question_answer 74)
Given that W = weight of load handled, W = weight of rope, and \[f=\] acceleration, the additional load in ropes of a hoist during starting is given by:
A)
\[{{F}_{a}}=\left( \frac{W-{{W}_{r}}}{g} \right)f\] done
clear
B)
\[{{F}_{a}}=\left( \frac{W+{{W}_{r}}}{g} \right)f\] done
clear
C)
\[{{F}_{a}}=\left( \frac{W}{g} \right)f\] done
clear
D)
\[{{F}_{a}}=\left( \frac{{{W}_{r}}}{g} \right)f\] done
clear
View Solution play_arrow
question_answer 75)
When a shaft transmits power through gears, the shaft experiences:
A)
Torsional stresses alone done
clear
B)
Bending stresses alone done
clear
C)
Constant bending and varying torsional stresses done
clear
D)
Varying bending and constant torsional stresses done
clear
View Solution play_arrow
question_answer 76)
The limiting wear load of spur gear is proportional to (where \[{{E}_{p}}\,\,=\] Young's modulus of union material; \[{{E}_{g}}\,\,=\] Young's modulus of gear material:
A)
\[{{({{E}_{p}}+{{E}_{g}})}^{-1}}\] done
clear
B)
\[\left( \frac{{{E}_{p}}+{{E}_{s}}}{{{E}_{p}}{{E}_{s}}} \right)\] done
clear
C)
\[\left( 1+\frac{{{E}_{p}}}{{{E}_{s}}} \right)\] done
clear
D)
\[\left( 1+\frac{{{E}_{g}}}{{{E}_{B}}} \right)\] done
clear
View Solution play_arrow
question_answer 77)
Which one of the following statements is not true of rolling contact bearing?
A)
The bearing characteristic number is given by \[\frac{ZN}{p}\] where Z is the absolute viscosity of the lubricant, Nis the shaft speed and p is the bearing pressure. done
clear
B)
Inner race of a radial ball bearing has an interference fit with the shaft and rotates along with it. done
clear
C)
Outer race of the hearing has in interference fit with bearing housing and does not rotate. done
clear
D)
In some cases, the inner race is stationary and outer race rotates. done
clear
View Solution play_arrow
question_answer 78)
In the multiple disc clutch, if there are 6 discs on the driving shaft and 5 discs on the driven shaft, then the number of pairs of contact surfaces will be equal to:
A)
11 done
clear
B)
12 done
clear
C)
10 done
clear
D)
22 done
clear
View Solution play_arrow
question_answer 79)
Match List-I with List-II and select the correct answer using the codes given below the lists:
List-I (Bearing materials) List-II (Properties) A. Babbits 1. Porous B. Bronze 2. Good emeddability C. C.I. 3. Suitable for high Loads and low speeds D. Sintered powdered metal 4 Run well with C.I. journals
Codes:
A)
A\[\to \]2, B\[\to \]3, C\[\to \]4, D\[\to \]1 done
clear
B)
A\[\to \]3, B\[\to \]2, C\[\to \]1, D\[\to \]4 done
clear
C)
A\[\to \]2, B\[\to \]3, C\[\to \]1, D\[\to \]4 done
clear
D)
A\[\to \]3, B\[\to \]2, C\[\to \]4, D\[\to \]1 done
clear
View Solution play_arrow
question_answer 80)
Wahl stress factor takes into account:
A)
Direct shear stress. done
clear
B)
Torsional shear stress done
clear
C)
Wire curvature effect done
clear
D)
Direct shear and wire curvature effect. done
clear
View Solution play_arrow
question_answer 81)
Which of the following stresses are associated with the tightening of nut on a bolt?
(1) Tensile stress due to the stretching of bolt (2) Bending stress due to the bending of bolt (3) Crushing and shear stresses in threads (4) Torsional shear stress due to frictional resistance between the nut and the bolt.
Select the correct answer using the codes given below:
A)
1, 2 and 4 done
clear
B)
1, 2 and 3 done
clear
C)
2, 3 and 4 done
clear
D)
1, 3 and 4 done
clear
View Solution play_arrow
question_answer 82)
The shearing area of a key of length 'L' breadth 'b' depth 'h' is equal to:
A)
\[b\times h\] done
clear
B)
\[L\times h\] done
clear
C)
\[L\times b\] done
clear
D)
\[L\times (h/2)\] done
clear
View Solution play_arrow
question_answer 83)
Match List-I (Machine element) with List-II (Cause of failure) and select the correct answer using the codes given below the lists:
List-I List-II A. Axle 1. Shear stress B. Cotter 2. Tensile/Compressive stress C. Connecting rod 3. Wear D. Journal bearing 4 Bending stress
Codes:
A)
A\[\to \]1, B\[\to \]4, C\[\to \]2, D\[\to \]3 done
clear
B)
A\[\to \]4, B\[\to \]1, C\[\to \]2, D\[\to \]3 done
clear
C)
A\[\to \]4, B\[\to \]1, C\[\to \]3, D\[\to \]2 done
clear
D)
A\[\to \]1, B\[\to \]4, C\[\to \]3, D\[\to \]2 done
clear
View Solution play_arrow
question_answer 84)
In oxy-acetylene gas welding, for complete combustion, the volume of oxygen required per unit of acetylene is:
A)
1 done
clear
B)
1.5 done
clear
C)
2 done
clear
D)
2.5 done
clear
View Solution play_arrow
question_answer 85)
Consider the following statements. A splined shaft is used for
1. Transmitting power 2. Holding a flywheel rigidly in position 3. Moving axially the gear wheels mounted on it 4. Mounting V-belt pulleys on it.
Of these statements:
A)
2 and 3 are correct done
clear
B)
1 and 4 are correct done
clear
C)
2 and 4 are correct done
clear
D)
1 and 3 are correct done
clear
View Solution play_arrow
question_answer 86)
When two shafts are neither parallel nor intersecting, power can be transmitted by using:
A)
A pair of spur gears done
clear
B)
A pair of helical gears done
clear
C)
An Oldham's coupling done
clear
D)
A pair of spiral gears. done
clear
View Solution play_arrow
question_answer 87)
In the assembly design of shaft, pulley and key, the weakest members is:
A)
Pulley done
clear
B)
Key done
clear
C)
Shaft done
clear
D)
None done
clear
View Solution play_arrow
question_answer 88)
In the formulation of Lewis equation for toothed gearing, it is assumed that tangential tooth load \[{{F}_{1}}\]act on the:
A)
Pitch point done
clear
B)
Tip of the tooth done
clear
C)
Root of the tooth done
clear
D)
Whole face of the tooth done
clear
View Solution play_arrow
question_answer 89)
For a two-dimensional state \[({{\sigma }_{1}},\,{{\sigma }_{2}},\,{{\sigma }_{1}}\]>\[0,\,{{\sigma }_{2}}\]<0) he designed values are most conservative if which one of the following failure theories were used?
A)
Maximum principal strain theory done
clear
B)
Maximum distortion energy theory done
clear
C)
Maximum shear stress theory done
clear
D)
Maximum principal stress theory done
clear
View Solution play_arrow
question_answer 90)
Match List-I with List-II and select the correct answer using the codes given below the lists:
List-I List-II A. Single-plate friction clutch 1. Scooters clutch B. Multi-plate friction clutch 2. Rolling mills C. Centrifugal clutch 3. Trucks D. Jaw clutch 4. Mopeds
Codes:
A)
A\[\to \]1, B\[\to \]3, C\[\to \]4, D\[\to \]2 done
clear
B)
A\[\to \]1, B\[\to \]3, C\[\to \]2, D\[\to \]4 done
clear
C)
A\[\to \]3, B\[\to \]1, C\[\to \]2, D\[\to \]4 done
clear
D)
A\[\to \]3, B\[\to \]1, C\[\to \]4, D\[\to \]2 done
clear
View Solution play_arrow
question_answer 91)
Which of the following stresses are associated with the design of pins in hushed pin-type, flexible coupling?
1. Bearing stress 2. Bending stress 3. Axial tensile stress 4. Transverse shear stress
Select the correct answer using the codes given below:
A)
1, 3 and 4 done
clear
B)
2, 3 and 4 done
clear
C)
1, 2 and 3 done
clear
D)
1, 2 and 4 done
clear
View Solution play_arrow
question_answer 92)
The diameter of tommy bar for a screw jack is designed for:
A)
Bending moment due to effort applied done
clear
B)
Torque on the tommy bar due to effort applied done
clear
C)
A percentage of axial loads done
clear
D)
Some axial loads coupled with transverse loads done
clear
View Solution play_arrow
question_answer 93)
Centrifugal tension in belts is:
A)
Useful because it maintains some tension even when no power is transmitted done
clear
B)
Not harmful because it does not take part in power transmission done
clear
C)
Harmful because it increases belt tension and reduces the power transmitted done
clear
D)
A hypothetical phenomenon and does not actually exist in belts done
clear
View Solution play_arrow
question_answer 94)
In a single reduction, a large velocity ratio is required. The best transmission is:
A)
Spur gear drive done
clear
B)
Helical gear drive done
clear
C)
Bevel gear drive done
clear
D)
Worm gear drive done
clear
View Solution play_arrow
question_answer 95)
Which one of the following belts should not he used above\[40{}^\circ C\]?
A)
Balata belt done
clear
B)
rubber belt done
clear
C)
Fabric belt done
clear
D)
synthetic belt done
clear
View Solution play_arrow
question_answer 96)
Consider the following statements:
A nomenclature \[\phi \]50H8/p8 denoted that 1. Hole diameter is 50 mm 2. It is a shaft base system 3. 8 indicates fundamental deviation.
Which of the statements given above is/are correct?
A)
1, 2 and 3 done
clear
B)
1 and 2 only done
clear
C)
1 and 3 only done
clear
D)
3 only done
clear
View Solution play_arrow
question_answer 97)
A certain minimum number of teeth is to be kept for a gear wheel:
A)
So that the gear is of a good size done
clear
B)
For better durability done
clear
C)
To avoid interference and undercutting done
clear
D)
For better strength done
clear
View Solution play_arrow
question_answer 98)
In a single row deep groove ball-bearing, cages are needed to:
A)
Separate the two races done
clear
B)
Separate the balls from the inner race done
clear
C)
Separate the outer race from the balls done
clear
D)
Ensure that the balls do into cluster at one point and maintain proper relative angular positions. done
clear
View Solution play_arrow
question_answer 99)
Which one of the following types of bearings is employed in shafts of gearboxes of automobiles?
A)
Hydrodynamic journal bearings done
clear
B)
Multi-lobed journal hearings done
clear
C)
Antifriction bearings done
clear
D)
Hybrid journal bearings. done
clear
View Solution play_arrow
question_answer 100)
A hole is to be punched in a 15 mm thick plate having an ultimate shear strength of 3 N-\[m{{m}^{-2}}.\]If the allowable crushing stress in the punch is \[6\,N\]-\[m{{m}^{-2}},\] the diameter of the smallest hole which can be punched is equal to:
A)
15 mm done
clear
B)
30 mm done
clear
C)
60 mm done
clear
D)
120 mm done
clear
View Solution play_arrow
question_answer 101)
The edge of a steel plate cut by oxygen cutting will get hardened when the carbon content is:
A)
Less than 0.1 percent done
clear
B)
Less than 0.3 percent done
clear
C)
More than 0.3 percent done
clear
D)
Anywhere between 0.1 to 1.0 percent done
clear
View Solution play_arrow
question_answer 102)
The safe rim velocity of a flywheel is influenced by the
A)
Centrifugal stresses done
clear
B)
Fluctuation of energy done
clear
C)
Fluctuation of speed done
clear
D)
Mass of the flywheel done
clear
View Solution play_arrow
question_answer 103)
Match List-I (Bearings) with List-II (Applications) and select the correct answer using the codes given below the lists:
List-I List-II A. Journal hearing 1. Electric motors B. Thrust bearing 2. Watches C. Conical pivot bearing 3. Marine engines D. Ball bearing 4. Swivelling chairs
Codes:
A)
A\[\to \]3, B\[\to \]4, C\[\to \]1, D\[\to \]2 done
clear
B)
A\[\to \]4, B\[\to \]2, C\[\to \]1, D\[\to \]3 done
clear
C)
A\[\to \]3, B\[\to \]4, C\[\to \]2, D\[\to \]1 done
clear
D)
A\[\to \]4, B\[\to \]2, C\[\to \]3, D\[\to \]1 done
clear
View Solution play_arrow
question_answer 104)
Weld spatter occurs due to any of the following except:
A)
High welding current done
clear
B)
Too small an electrode done
clear
C)
Are done
clear
D)
Wrong polarity done
clear
View Solution play_arrow
question_answer 105)
In a hydrodynamic journal bearing, there is:
A)
A very thin film of lubricant between the journal and the hearing such that there is contact between the journal and the bearing done
clear
B)
A thick film of lubricant between the journal and the bearing done
clear
C)
No lubricant between the journal and the bearing done
clear
D)
A forced lubricant between the journal and the bearing done
clear
View Solution play_arrow
question_answer 106)
Consider the following statements:
1. From design considerations, it is always advantageous to place cast iron ribs on the tension side rather than on the compression side. 2. Cast iron is an excellent choice for machine tool guides and frames 3. Cast iron parts have a low notch sensitivity.
Which of these statements are correct?
A)
1, 2 and 3 done
clear
B)
2 and 3 done
clear
C)
1 and 3 done
clear
D)
1 and 2 done
clear
View Solution play_arrow
question_answer 107)
Match List-I (Applications) with List-II (Choice of bearings) and select the correct answer using the codes given below the lists:
List-I (Application) List-II (Choice of Bearings) A. Granite table of a coordinate measuring machine 1. Hydrodynamic bearing B. Headstock spindle of a lathe 2. Deep groove ball bearing C. Crank shaft of a lathe 3. hydrostatic bearing diesel engine D. Armature of 0.5 kW induction motor 4. Taper roller bearing
Codes:
A)
A\[\to \]1, B\[\to \]4, C\[\to \]3, D\[\to \]2 done
clear
B)
A\[\to \]3, B\[\to \]2, C\[\to \]1, D\[\to \]4 done
clear
C)
A\[\to \]1, B\[\to \]2, C\[\to \]3, D\[\to \]4 done
clear
D)
A\[\to \]3, B\[\to \]4, C\[\to \]1, D\[\to \]2 done
clear
View Solution play_arrow
question_answer 108)
If k = 3 for hail bearings and k = 3.33 for roller bearings, which one of the following correctly states the load (P) - Life (L) relationship for rolling contact bearings?
A)
\[\frac{{{L}_{1}}}{{{L}_{2}}}\,=\,{{\left( \frac{{{p}_{1}}}{{{p}_{2}}} \right)}^{k}}\] done
clear
B)
\[\frac{{{L}_{1}}}{{{L}_{2}}}\,=\,{{\left( \frac{{{p}_{1}}}{{{p}_{2}}} \right)}^{\frac{1}{(k-1)}}}\] done
clear
C)
\[\frac{{{L}_{2}}}{{{L}_{1}}}\,=\,{{\left( \frac{{{p}_{1}}}{{{p}_{2}}} \right)}^{k}}\] done
clear
D)
\[\frac{{{L}_{2}}}{{{L}_{1}}}\,=\,{{\left( \frac{{{p}_{1}}}{{{p}_{2}}} \right)}^{k-1}}\] done
clear
View Solution play_arrow
question_answer 109)
Consider the following statements regarding boundary lubrication conditions in hydrodynamic journal hearings:
1. It is an undesirable condition. 2. It always occurs during starting and stopping of the journal. 3. It necessitates frequent repair of the journal. 4. This condition can he completely eliminated by using high viscosity lubricant.
Which of the statements given above are correct?
A)
1, 2 and 4 done
clear
B)
2, 3 and 4 done
clear
C)
1 and 2 done
clear
D)
3 and 4 done
clear
View Solution play_arrow
question_answer 110)
When the lubricating oil is forced between the journal and bearing by external pressure, the bearing is known as:
A)
Zero film bearing done
clear
B)
Boundary lubricated bearing done
clear
C)
Hydrostatic bearing done
clear
D)
Hydrodynamic bearing done
clear
View Solution play_arrow
question_answer 111)
Intensity of radiation at a surface in perpendicular direction is equal to:
A)
Product of emissivity of surface and \[1/\pi .\] done
clear
B)
Product of emissivity of surface and \[\pi .\] done
clear
C)
Product of emissive power of surface and \[1/\pi .\] done
clear
D)
Product of emissive power of surface and \[\pi .\] done
clear
View Solution play_arrow
question_answer 112)
In a mass transfer process of diffusion of hot smoke in cold air in a power plant, the temperature profile and the concentration profile will become identical when:
A)
Prandtl No. = 1 done
clear
B)
Nusselt No. = 1 done
clear
C)
Lewis No. = 1 done
clear
D)
Schemidt No. = 1 done
clear
View Solution play_arrow
question_answer 113)
Witch one of the following numbers represents the ratio of kinematic viscosity to the thermal diftusivity?
A)
Grashoff number done
clear
B)
Prandtl number done
clear
C)
Mach number done
clear
D)
Nusselt number. done
clear
View Solution play_arrow
question_answer 114)
After expansion from a gas turbine, the hot exhaust gases are used to heat the compressed air from a compressor with the help of a cross flow compact heat exchanger of 0.8 effectiveness. What is the number of transfer units of the heat exchanger?
A)
2 done
clear
B)
4 done
clear
C)
8 done
clear
D)
16 done
clear
View Solution play_arrow
question_answer 115)
A thin flat Plate \[2\,m\,\times \,2\,m\] is hanging freely in air. The temperature of the surrounding is \[25{}^\circ C.\] Solar radiation is falling on one side of the plate at the rate of 500 \[W/{{m}^{2}}.\] What should be the convective heat Transfer coefficient in \[W/{{m}^{2}}{}^\circ C,\] if the temperature of The plate is to remain constant at \[30{}^\circ C?\]
A)
25 done
clear
B)
50 done
clear
C)
100 done
clear
D)
200 done
clear
View Solution play_arrow
question_answer 116)
In order to achieve maximum heat dissipation, the fin should be designed in such a way that:
A)
It should have maximum lateral surface at the root side of the fin done
clear
B)
It should have maximum lateral surface towards the tip side of the fin done
clear
C)
It should have maximum lateral surface near the centre of the fin done
clear
D)
It should have minimum lateral surface near the centre of the fin. done
clear
View Solution play_arrow
question_answer 117)
A composite hollow sphere with steady internal heating is made of 2 layers of materials of equal thickness with thermal conductivities in the ratio of' 1:2 for inner to outer layers. Ratio of inside to outside diameter is 0.8. What is ratio of temperature drop across the inner and outer layers?
A)
0.4 done
clear
B)
1.6 done
clear
C)
2 in 0.8 done
clear
D)
2.5 done
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question_answer 118)
Upto the critical radius of insulation:
A)
Added insulation increases heat loss. done
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B)
Added insulation decreases heat loss. done
clear
C)
Convection heat loss is less than conduction heat loss. done
clear
D)
Heat flux decreases. done
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question_answer 119)
Match List-I (Governing Equations of Heat Transfer) with List-II (Specific Case of Heat Transfer) and select the correct answer using the code given below the lists:
List-I (Governing Equations of Heat Transfer) List-II (Specific Cass of Heat Transfer) A. \[\frac{{{d}^{2}}T}{d{{r}^{2}}}\,+\,\frac{2dT}{rdr}\,=\,0\] 1. Pin fin 1-D case B. \[\frac{{{\partial }^{2}}T}{\partial {{x}^{2}}}\,+\,\frac{1}{\alpha }\,\frac{\partial T}{dt}\] 2. 1-D conduction in cylinder C. \[\frac{{{d}^{2}}T}{d{{r}^{2}}}\,+\,\frac{1}{r}\,\frac{dT}{dr}\,=\,0\] 3. 1-D conduction in sphere D. \[\frac{{{d}^{2}}\theta }{d{{x}^{2}}}-{{m}^{2}}\theta =0\] 4. Plane slab
Codes:
A)
A\[\to \]2, B\[\to \]4, C\[\to \]3, D\[\to \]1 done
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B)
A\[\to \]3, B\[\to \]1, C\[\to \]2, D\[\to \]4 done
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C)
A\[\to \]2, B\[\to \]1, C\[\to \]3, D\[\to \]4 done
clear
D)
A\[\to \]3, B\[\to \]4, C\[\to \]2, D\[\to \]1 done
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question_answer 120)
6.0 kJ of conduction heat transfer has to take place in 10 minutes from one end to other end of a metallic cylinder of 10 cm cross-sectional area, length 1 metre and thermal conductivity as 100 W/m.K. What is the temperature difference between the two ends of the cylindrical bar?
A)
\[80{}^\circ C\] done
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B)
\[100{}^\circ C\] done
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C)
\[120{}^\circ C\] done
clear
D)
\[160{}^\circ C\] done
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