⚙️Mechanical Engineering MCQs
Mechanical Engineering MCQs
488 MCQs291
One kg of steam sample contains 0.8 kg dry steam; it’s dryness fraction is__________________?
A0.2
B0.8
C1.0
D0.6 E. 0.5
292
Sublimation region is the region where__________________?
Asolid and vapour phases are in equi-librium
Bsolid and liquid phases are in equilibrium
Cliquid and vapour phases are in equilibrium
Dsolid, liquid and vapour phases are in equilibrium E. none of the above
293
Choose the correct relationship ?
Aspecific gravity = gravity x density
Bdynamicviscosity = kinematicviscosity x density
Cgravity = specific gravity x density
Dkinematicviscosity = dynamicviscosity x density E. hydrostaticforce = surface tension x gravity
294
Hygrometery deals with the_________________?
AHygroscopic substances
Bwater vapour in air
Ctemperature of air
Dpressure of air E. density measurement
295
The increase in pressure _________________?
Alowers the boiling point of a liquid
Braises the boiling point of a liquid
C.does not affect the boiling point of a liquid
Dreduces its volume E. none of the above
296
Pick up the wrong statement?
Aaluminium in steel results in excessive grain growth
Bmanganese in steel induces hardness
Cnickel and chromium in steel help in raising the elastic limit and improve the resilience and ductility
Dtungsten in steels improves magnetic properties and hardenability E. sulphur, phosphorous and lead im¬prove machining properties of steel
297
Carbonation of coal is the process of________________________?
Apulverising coal in inert atmosphere
Bheating wood in a limited supply of air at temperatures below 300°C
Cstrongly heating coal continuously for about 48 hours in the absence of air in a closed vessel
Dbinding the pulverised coal into brick-ettes E. enriching carbon in the coal
298
The latent heat of steam at pressures greater than atmospheric in comparison to latent heat at atmospheric pressure is__________________?
Aless
Bmore
Cequal
Dmay be less or more depending on temperature E. unpredictable
299
At very low temperature, the melting and boiling temperatures become equal. This temperature is____________________?
A373°K
B273.16°K
C303°K
D0°K. E. 300°K
300
Pick up false statement?
AFor petrol and large gas engines, quantity governingds preferred
BIn quantity governing, air fuel ratio is almost constant and quantity of charge is changed depending on load
CIn hit and miss governing, fuel supply is completely cut off during one or more number of cycles
DIn quality governing, quantity of fuel is varied to suit the load and total charge of air is varied E. For close regulation of speed, combination of both quality and quantity governing is used