At the time of starting, idling and low speed operation, the carburetor supplies a mixture which can be termed as

slightly leaner than stociometric

For constant maximum pressure and same heat input

\({\eta _{otto}} > {\eta _{diesel}} > {\eta _{dual}}\)

\({\eta _{diesel}} > {\eta _{otto}} > {\eta _{dual}}\)

\({\eta _{otto}} > {\eta _{dual}} > {\eta _{diesel}}\)

\({\eta _{diesel}} > {\eta _{dual}} > {\eta _{otto}}\)

Air-cooled engine’s efficiency is _______ than/as a water-cooled engine for the same power rating.

more or less depends upon operation

For the same maximum, pressure and temperature

Dual cycle is more efficient than Otto and Diesel cycles

Otto cycle is more efficient than Diesel cycle

Diesel cycle is more efficient than Otto cycle

Dual cycle is more efficient than Otto and Diesel cycles

Dual cycle is less efficient than Otto and Diesel cycles

Explore topic-wise MCQs in Mechanical Engineering.

This section includes 14 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.	In reciprocating engines, the ratio of volume at bottom dead center to the volume at top dead center is called
A.	efficiency ratio
B.	compression ratio
C.	failure ratio
D.	demand ratio
Answer» C. failure ratio

Discussion

2.	Brake thermal efficiency of a 15 kW IC engine is 30%. If the fuel used has CV 40 MJ/kg, then the fuel consumption rate in kg/h is:
A.	4.5
B.	1
C.	3
D.	2.5
Answer» B. 1

Discussion

3.	During suction of air in CI engine, the pressure in cylinder will be _______ atmospheric:
A.	less than
B.	more than
C.	more or less as
D.	equal to
Answer» B. more than

Discussion

4.	A two-stroke engine consists of ______ port(s).
A.	Three
B.	One
C.	Four
D.	Two
Answer» B. One

Discussion

5.	At the time of starting, idling and low speed operation, the carburetor supplies a mixture which can be termed as
A.	lean
B.	slightly leaner than stociometric
C.	stochiometric
D.	rich
Answer» E.

Discussion

6.	For constant maximum pressure and same heat input
A.	\({\eta _{otto}} > {\eta _{diesel}} > {\eta _{dual}}\)
B.	\({\eta _{diesel}} > {\eta _{otto}} > {\eta _{dual}}\)
C.	\({\eta _{otto}} > {\eta _{dual}} > {\eta _{diesel}}\)
D.	\({\eta _{diesel}} > {\eta _{dual}} > {\eta _{otto}}\)
Answer» E.

Discussion

7.	Nominal volume generated by the working piston when travelling from one dead centre to the next is called _____.
A.	clearance volume
B.	swept volume
C.	total volume
D.	stroke volume
Answer» C. total volume

Discussion

8.	A Mercedes – Benz car engine has swept volume of 300 cc and clearance of 25 cc. Its volumetric efficiency is 0.88 and mechanical efficiency is 0.90. The volume of mixture taken in per stroke is:
A.	198 cc
B.	264 cc
C.	164 cc
D.	284 cc
Answer» C. 164 cc

Discussion

9.	Air enters diesel engine with a density of 1 kg/m3. The compression ratio is 21. At steady state, the air intake is 21 × 10-3 kg/s and the network output is 20 kW. The Mean effective pressure (kPa) is
A.	500
B.	1000
C.	1500
D.	2000
Answer» C. 1500

Discussion

10.	In a 4-stroke petrol engine, the actual volume of fresh charge admitted is:
A.	less than stroke volume
B.	equal to stroke volume
C.	equal to clearance volume
D.	more than stroke volume
Answer» B. equal to stroke volume

Discussion

11.	Air-cooled engine’s efficiency is _______ than/as a water-cooled engine for the same power rating.
A.	same
B.	more
C.	less
D.	more or less depends upon operation
Answer» D. more or less depends upon operation

Discussion

12.	For the same maximum, pressure and temperature
A.	Otto cycle is more efficient than Diesel cycle
B.	Diesel cycle is more efficient than Otto cycle
C.	Dual cycle is more efficient than Otto and Diesel cycles
D.	Dual cycle is less efficient than Otto and Diesel cycles
Answer» C. Dual cycle is more efficient than Otto and Diesel cycles

Discussion

13.	In air standard assumptions, all the processes that make up the cycle are internally
A.	reversible
B.	irreversible
C.	heated
D.	cooled
Answer» B. irreversible

Discussion

14.	A cycle consisting of two constant volumes and two isothermal processes is known as
A.	Carnot cycle
B.	Diesel cycle
C.	Joule cycle
D.	Stirling cycle
Answer» E.

Discussion

Explore topic-wise MCQs in Mechanical Engineering.

In reciprocating engines, the ratio of volume at bottom dead center to the volume at top dead center is called

Brake thermal efficiency of a 15 kW IC engine is 30%. If the fuel used has CV 40 MJ/kg, then the fuel consumption rate in kg/h is:

During suction of air in CI engine, the pressure in cylinder will be _______ atmospheric:

A two-stroke engine consists of ______ port(s).

At the time of starting, idling and low speed operation, the carburetor supplies a mixture which can be termed as

For constant maximum pressure and same heat input

Nominal volume generated by the working piston when travelling from one dead centre to the next is called _____.

A Mercedes – Benz car engine has swept volume of 300 cc and clearance of 25 cc. Its volumetric efficiency is 0.88 and mechanical efficiency is 0.90. The volume of mixture taken in per stroke is:

Air enters diesel engine with a density of 1 kg/m3. The compression ratio is 21. At steady state, the air intake is 21 × 10-3 kg/s and the network output is 20 kW. The Mean effective pressure (kPa) is

In a 4-stroke petrol engine, the actual volume of fresh charge admitted is:

Air-cooled engine’s efficiency is _______ than/as a water-cooled engine for the same power rating.

For the same maximum, pressure and temperature

In air standard assumptions, all the processes that make up the cycle are internally

A cycle consisting of two constant volumes and two isothermal processes is known as