GATE ME 1992
GATE ME
1
Instantaneous centre of a body rolling with sliding on a stationary curved surface lies.
2
A Venturimeter (throat diameter $$=10.5$$ $$cm$$) is fitted to a water pipe line (internal diameter $$=21.0$$ $$cm$$) in order to monitor flow rate. To improve accuracy of measurement, pressure difference across the venturimeter is measured with the help of an inclined tube manometer, the angle of inclination being $${30^0}$$ (see figure below). For manometer reading of $$9.5$$ $$cm$$ of mercury, find the flow rate.Discharge coefficient of venture is $$0.984.$$
3
A fluid flowing over a flat plate has the following properties: dynamic viscocity $$ = 25 \times {10^{ - 6}}\,\,kg/ms,$$ specific heat $$=2.0 $$ $$kJ/kgK,$$ thermal conductivity $$0.05W/mK.$$ The hydrodynamic boundary layer thickness is measured to be $$0.5$$ $$mm.$$ The thickness of the thermal boundary layer would be
4
Two rods, one of length $$L$$ and the other of length $$2L$$ are made of the same material and have the same diameter. The two ends of the longer rod are maintained at $${100^ \circ }C.$$ One end of the shorter end is maintained at $${100^ \circ }C.$$ while the other end is insulated. Both the rods are exposed to the same environment at $${40^ \circ }C.$$ The temperature at the insulated end of the shorter rod is measured to be $${55^ \circ }C.$$ The temperature at the mid-point of the longer rod would be
5
Starting friction is low in
6
Spherical roller bearings are normally used
7
Fatigue strength of a rod subjected to cyclic axial force is less than that of a rotating beam of the same dimensions subjected to steady lateral force because
8
A large uniform plate containing a rivet hole is subjected to uniform uniaxial tension of $$95$$ $$MPa.$$ The maximum stress in the plate is
9
In $$PTP$$ type of $$NC$$ system
10
Two shafts $$A$$ and $$B$$ have their diameters specified as $$100 \pm 0.1\,\,mm$$ and $$0.1 \pm 0.0001\,\,mm$$ respectively. Which of the following statements is/are true
11
The thickness of the blank needed to produce, by power spinning a missile cone of thickness $$1.5mm$$ and half cone angle $$30deg$$
12
Component process
13
In horizontal milling process ............................ (up/down) milling provides better surface finish and .............................. Up/down ) milling provide longer tool life.
14
In an orthogonal cutting operation on a work piece of width $$2.5mm,$$ the uncut chip thickness was $$0.25$$ $$mm$$ and the tool rake angle was $$0$$(zero) degrees. It was observed that the chip thickness was $$1.25mm.$$ The cutting force was measured to be $$900N$$ and the thrust force was found to be $$450N.$$ Find the mean shear strength of the work piece material and if the coefficient of friction between the chip and the tool was $$0.5,$$ what is the machining constant.
15
The effect of rake angle on the mean friction angle in machining can be explained by
16
A low carbon steel is to be welded by the manual metal arc welding process using a linear $$V$$-$$I$$ characteristic $$DC$$ power source.
The following data is available.
$$O.C$$ voltage of the power source $$=62V,$$
$$S.C$$ current for the setting used $$=130A,$$
ARC length $$=4mm,$$
Traverse speed of welding $$=15cm/min$$
Efficiency of heat input $$ = 85\% $$
The relation between the arc length $$L$$ in $$mm$$
and arc voltage $$V$$ is $$V=20+1.5L$$
Calculate the heat input into the work piece.
17
In an explosive welding process, the ..................... (maximum/minimum) velocity of impact is fixed by the velocity of sound in the ............. (flyer / target) plate material.
18
For resistance spot welding of $$1.5$$ $$mm$$ thick steel sheets, the current required is of the order
19
The true strain for a low carbon steel bar which is doubled in length by forging is
20
Calculate the ratio of the solidification times of two steel cylindrical risers of sizes $$30cm$$ diameter by $$60$$ $$cm$$ in height and $$60cm$$ diameter by $$30$$ $$cm$$ in height subjected to identical conditions of cooling
21
Match the following:
22
In a green sand moulding process, uniform ramming leads to
23
A block of steel is loaded by a tangential force on its top surface while the bottom surface is held rigidly. The deformation of the block is due to
24
A large uniform plate containing a rivet-hole is subjected to uniform uniaxial tension of 95 MPa. The maximum stress in the plate is
25
Instantaneous center of a body rolling with sliding on a stationary curved surface lies
26
A steam turbine operating with less moisture is ____________ (more/less) efficient and ________ (less/more) prone to blade damage.
27
In a steam power plant operating with simple Rankine cycle, the turbine is fed with steam at $$100$$ bar and $$673$$ $$K.$$ Determine the actual enthalpy and quality of the steam extracted at $$14$$ bar if the turbine stage efficiency is $$90$$ percent.
28
Subsonic and supersonic diffusers have the following geometry:
29
In stream and other vapor cycles, the process of removing non-condensables is called
30
Boiler rating is usually defined in terms of:
31
A condenser of a refrigeration system rejects heat at a rate of $$120$$ $$kW,$$ while its compressor consumes a power of $$30$$ $$kW.$$ The coefficient of performance of the system would be
32
A Hydro turbine is required to give $$25$$ $$MW$$ at $$50$$ $$m$$ head and $$90$$ $$rpm$$ runner speed. The laboratory facilities available, permit testing of $$20$$ $$kW$$ models at $$5$$ $$m$$ head. What should be the model runner speed and model to prototype scale ratio?