4791 + Mcqs in Mechanical Engineering Page 6 McqOptions

251.	A single point thread cutting tool should ideally have
A.	zero rake angle
B.	positive rake angle
C.	negative rake angle
D.	point angle
Answer» B. positive rake angle

Discussion

252.	The work or surface speed for cylindrical grinding varies from
A.	5 to 10 m/min
B.	10 to 20 m/min
C.	20 to 30 m/min
D.	40 to 60 m/min
Answer» D. 40 to 60 m/min

Discussion

253.	In order to prevent tool from rubbing the work __________ on tools are provided.
A.	rake angles
B.	relief angles
Answer» C.

Discussion

254.	A fine grained grinding wheel is used to grind hard materials.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

255.	Euler's formula holds good only for
A.	short columns
B.	long columns
C.	both short and long columns
D.	weak columns
Answer» C. both short and long columns

Discussion

256.	A vertical column has two moments of inertia (i.e. Ixx and Iyy ). The column will tend to buckle in the direction of the
A.	axis of load
B.	perpendicular to the axis of load
C.	maximum moment of inertia
D.	minimum moment of inertia
Answer» E.

Discussion

257.	The object of caulking in a riveted joint is to make the joint
A.	free from corrosion
B.	stronger in tension
C.	free from stresses
D.	leak-proof
Answer» E.

Discussion

258.	Gantt chart is used for
A.	inventory control
B.	material handling
C.	production schedule
D.	machine repair schedules
Answer» D. machine repair schedules

Discussion

259.	The main object of scientific layout is
A.	to produce better quality of product
B.	to utilise maximum floor area
C.	to minimise production delays
D.	all of these
Answer» E.

Discussion

260.	The probabilistic time is given by (where to = Optimistic time, tp = Pessimistic time, and tn = Most likely time)
A.	<img src="/_files/images/mechanical-engineering/industrial-engineering-and-production-management/741-71-1.png">
B.	<img src="/_files/images/mechanical-engineering/industrial-engineering-and-production-management/741-71-2.png">
C.	<img src="/_files/images/mechanical-engineering/industrial-engineering-and-production-management/741-71-3.png">
D.	<img src="/_files/images/mechanical-engineering/industrial-engineering-and-production-management/741-71-4.png">
Answer» E.

Discussion

261.	Segmental chips are formed during machining
A.	mild steel
B.	cast iron
C.	high speed steel
D.	high carbon steel
Answer» C. high speed steel

Discussion

262.	Internal gears can be made by
A.	hobbing
B.	shaping with pinion cutter
C.	shaping with rack cutter
D.	milling
Answer» C. shaping with rack cutter

Discussion

263.	Cemented carbide tool tips are produced by powder metallurgy.
A.	True
B.	False
Answer» B. False

Discussion

264.	Side rake angle of a single point cutting tool is the angle
A.	by which the face of the tool is inclined towards back
B.	by which the face of the tool is inclined sideways
C.	between the surface of the flank immediately below the point and a plane at right angles to the centre line of the point of the tool
D.	between the surface of the flank immediately below the point and a line drawn from the point perpendicular to the base
Answer» C. between the surface of the flank immediately below the point and a plane at right angles to the centre line of the point of the tool

Discussion

265.	If the diameter of the hole is subject to considerable variation, then for locating in jigs and fixtures, the pressure type of locator used is
A.	conical locator
B.	cylindrical locator
C.	diamond pin locator
D.	vee locator
Answer» B. cylindrical locator

Discussion

266.	In the aircraft propellers
A.	the propulsive matter is ejected from within the propelled body
B.	the propulsive matter is caused to flow around the propelled body
C.	its functioning does not depend upon the presence of air
D.	none of the above
Answer» B. the propulsive matter is caused to flow around the propelled body

Discussion

267.	Intercooling in multi-stage compressors is done
A.	to cool the air during compression
B.	to cool the air at delivery
C.	to enable compression in two stages
D.	to minimise the work of compression
Answer» E.

Discussion

268.	A closed cycle gas turbine gives __________ efficiency as compared to an open cycle gas turbine.
A.	same
B.	lower
C.	higher
Answer» D.

Discussion

269.	Gas turbine as compared to steam turbine
A.	requires less space for installation
B.	has compressor and combustion chamber
C.	has less efficiency
D.	all of these
Answer» E.

Discussion

270.	The ratio of workdone per cycle to the stroke volume of the compressor is known as
A.	compressor capacity
B.	compression ratio
C.	compressor efficiency
D.	mean effective pressure
Answer» E.

Discussion

271.	The clearance volume in the compressor is kept minimum because it effects on volumetric efficiency.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

272.	A large clearance Volume in a reciprocating compressor results in
A.	reduced volume flow rate
B.	increased volume flow rate
C.	lower suction pressure
D.	lower delivery pressure
Answer» B. increased volume flow rate

Discussion

273.	Intercooling in gas turbines
A.	decreases net output but increases thermal efficiency
B.	increases net output but decreases thermal efficiency
C.	decreases net output and thermal efficiency both
D.	increases net output and thermal efficiency both
Answer» C. decreases net output and thermal efficiency both

Discussion

274.	In a single acting reciprocating compressor, the suction, compression and delivery of air takes place in __________ of the piston.
A.	one stroke
B.	two strokes
C.	three strokes
D.	four strokes
Answer» C. three strokes

Discussion

275.	The increase in pressure in a vane blower takes place first due to compression and then due to back flow of air.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

276.	While designing the refrigeration system of an aircraft, the prime consideration is that the
A.	system has high C.O.P.
B.	power per TR is low
C.	mass of refrigerant circulated in the system is low
D.	mass of the refrigeration equipment is low
Answer» E.

Discussion

277.	The heat transfer takes place according to
A.	Zeroth law of thermodynamics
B.	First law of thermodynamics
C.	Second law of thermodynamics
D.	Kirchhoff's law
Answer» D. Kirchhoff's law

Discussion

278.	An electrolux refrigerator is called a __________ absorption system.
A.	single fluid
B.	two fluids
C.	three fluids
Answer» D.

Discussion

279.	The type of rotary compressor used in gas turbines, is of
A.	centrifugal type
B.	axial flow type
C.	radial flow type
D.	none of these
Answer» C. radial flow type

Discussion

280.	The heat transfer by radiation __________ a medium.
A.	requires
B.	does not require
Answer» C.

Discussion

281.	Thermal conductivity of water __________ with rise in temperature.
A.	remains same
B.	decreases
C.	increases
D.	may increase or decrease depending upon temperature
Answer» E.

Discussion

282.	In case of solids, the heat transfer takes place according to radiation.
A.	Correct
B.	Incorrect
Answer» C.

Discussion

283.	The critical radius is the insulation radius at which the resistance to heat flow is
A.	maximum
B.	minimum
C.	zero
D.	none of these
Answer» C. zero

Discussion

284.	During a refrigeration cycle, heat is rejected by the refrigerant in a
A.	compressor
B.	condenser
C.	evaporator
D.	expansion valve
Answer» C. evaporator

Discussion

285.	A water cooled condenser operates at a __________ condensing temperature than an air-cooled condenser.
A.	higher
B.	lower
Answer» C.

Discussion

286.	The relative humidity decreases as air gets wet.
A.	True
B.	False
Answer» B. False

Discussion

287.	The temperature of ammonia after compression in a vapour compression system is
A.	20 to 50 C
B.	50 to 70 C
C.	70 to 110 C
D.	none of these
Answer» D. none of these

Discussion

288.	The subcooling in a refrigeration cycle
A.	does not alter C.O.P.
B.	increases C.O.P.
C.	decreases C.O.P.
D.	none of these
Answer» C. decreases C.O.P.

Discussion

289.	Nusselt number (NN) is given by
A.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/410-83-1.png">
B.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/410-83-2.png">
C.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/410-83-3.png">
D.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/410-83-4.png">
Answer» B. <img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/410-83-2.png">

Discussion

290.	The thickness of thermal and hydrodynamic boundary layer is equal if Prandtl number is
A.	equal to one
B.	greater than one
C.	less than one
D.	equal to Nusselt number
Answer» B. greater than one

Discussion

291.	During sensible cooling of air __________ decreases.
A.	wet bulb temperature
B.	relative humidity
C.	dry bulb temperature
D.	specific humidity
Answer» D. specific humidity

Discussion

292.	Which of the following represents a heat pump?
A.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/414-133-1.png">
B.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/414-133-2.png">
C.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/414-133-3.png">
D.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/414-133-4.png">
Answer» C. <img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/414-133-3.png">

Discussion

293.	In a psychrometric process, the sensible heat added is 30 kJ/s and the latent heat added is 20 kJ/s. The sensible heat factor for the process will be
A.	0.3
B.	0.6
C.	0.67
D.	1.5
Answer» C. 0.67

Discussion

294.	The formation of frost on cooling coils in a refrigerator
A.	increases heat transfer
B.	improves C.O.P. of the system
C.	increases power consumption
D.	reduces power consumption
Answer» D. reduces power consumption

Discussion

295.	The amount of radiation mainly depends upon the
A.	nature of the body
B.	temperature of the body
C.	type of surface of the body
D.	all of these
Answer» E.

Discussion

296.	For ammonia refrigerating systems, the tubes of a shell and tube condenser are made of
A.	copper
B.	aluminium
C.	steel
D.	brass
Answer» D. brass

Discussion

297.	The highest thermal diffusivity is of
A.	iron
B.	lead
C.	concrete
D.	wood
Answer» C. concrete

Discussion

298.	The angle included between the two lips projected upon a plane parallel to the drill axis and paralled to the two cutting lips, is called helix angle.
A.	Correct
B.	Incorrect
Answer» C.

Discussion

299.	The wet bulb temperature lines, on the psychrometric chart, are curved lines.
A.	True
B.	False
Answer» C.

Discussion

300.	The sensible heat factor during cooling and dehumidification process is given by (where h1 = Enthalpy of air entering the cooling coil, h2 = Enthalpy of air leaving the cooling coil, and hA = Enthalpy of air at the end of dehumidification process)
A.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/434-375-1.png">
B.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/434-375-2.png">
C.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/434-375-3.png">
D.	<img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/434-375-4.png">
Answer» B. <img src="/_files/images/mechanical-engineering/heat-transfer-refrigeration-and-air-conditioning/434-375-2.png">

Discussion

Explore topic-wise MCQs in Engineering.

A single point thread cutting tool should ideally have

The work or surface speed for cylindrical grinding varies from

In order to prevent tool from rubbing the work __________ on tools are provided.

A fine grained grinding wheel is used to grind hard materials.

Euler's formula holds good only for

A vertical column has two moments of inertia (i.e. Ixx and Iyy ). The column will tend to buckle in the direction of the

The object of caulking in a riveted joint is to make the joint

Gantt chart is used for

The main object of scientific layout is

The probabilistic time is given by (where to = Optimistic time, tp = Pessimistic time, and tn = Most likely time)

Segmental chips are formed during machining

Internal gears can be made by

Cemented carbide tool tips are produced by powder metallurgy.

Side rake angle of a single point cutting tool is the angle

If the diameter of the hole is subject to considerable variation, then for locating in jigs and fixtures, the pressure type of locator used is

In the aircraft propellers

Intercooling in multi-stage compressors is done

A closed cycle gas turbine gives __________ efficiency as compared to an open cycle gas turbine.

Gas turbine as compared to steam turbine

The ratio of workdone per cycle to the stroke volume of the compressor is known as

The clearance volume in the compressor is kept minimum because it effects on volumetric efficiency.

A large clearance Volume in a reciprocating compressor results in

Intercooling in gas turbines

In a single acting reciprocating compressor, the suction, compression and delivery of air takes place in __________ of the piston.

The increase in pressure in a vane blower takes place first due to compression and then due to back flow of air.

While designing the refrigeration system of an aircraft, the prime consideration is that the

The heat transfer takes place according to

An electrolux refrigerator is called a __________ absorption system.

The type of rotary compressor used in gas turbines, is of

The heat transfer by radiation __________ a medium.

Thermal conductivity of water __________ with rise in temperature.

In case of solids, the heat transfer takes place according to radiation.

The critical radius is the insulation radius at which the resistance to heat flow is

During a refrigeration cycle, heat is rejected by the refrigerant in a

A water cooled condenser operates at a __________ condensing temperature than an air-cooled condenser.

The relative humidity decreases as air gets wet.

The temperature of ammonia after compression in a vapour compression system is

The subcooling in a refrigeration cycle

Nusselt number (NN) is given by

The thickness of thermal and hydrodynamic boundary layer is equal if Prandtl number is

During sensible cooling of air __________ decreases.

Which of the following represents a heat pump?

In a psychrometric process, the sensible heat added is 30 kJ/s and the latent heat added is 20 kJ/s. The sensible heat factor for the process will be

The formation of frost on cooling coils in a refrigerator

The amount of radiation mainly depends upon the

For ammonia refrigerating systems, the tubes of a shell and tube condenser are made of

The highest thermal diffusivity is of

The angle included between the two lips projected upon a plane parallel to the drill axis and paralled to the two cutting lips, is called helix angle.

The wet bulb temperature lines, on the psychrometric chart, are curved lines.

The sensible heat factor during cooling and dehumidification process is given by (where h1 = Enthalpy of air entering the cooling coil, h2 = Enthalpy of air leaving the cooling coil, and hA = Enthalpy of air at the end of dehumidification process)