Skip to content

VideRime Online Learning

Search for:

Home
GK/GA MCQs
Questions?
- Ask Question
- Questions
Direct Links
Submit Article
Contact Us
Membership Registration
Login
Signup Now

Home
GK/GA MCQs
Questions?
- Ask Question
- Questions
Direct Links
Submit Article
Contact Us
Membership Registration
Login
Signup Now

IC Engines
0

IC Engines Practice Set-1

September 5, 2021

Show paginator

Hide paginator

25%

Page 1 of 4

1. The knocking in spark ignition engines can be reduced by

(B) Increasing the engine speed

(A) Retarding the spark

(D) None of these

(C) Both (A) and (B)

2. In a four stroke cycle diesel engine, the compression

Starts at top dead center and ends at 40° before bottom dead center

Starts at 40° after bottom dead center and ends at 10° before top dead center

Starts at 40° before top dead center and ends at 40° after top dead center

May start and end anywhere

3. An engine indicator is used to determine the following

Temperature

Speed

Volume of cylinder

m.e.p. and I.H.P.

4. The fuels in order of decreasing knock tendency for spark ignition engines are

Paraffin, napthene, aromatic

Napthene, paraffin, aromatic

Napthene, aromatics, paraffin

Paraffin, aromatic, napthene

5. The maximum temperature in the I.C. engine cylinder is of the order of

500-1000°C

1000-1500°C

2000-2500°C

1500-2000°C

6. In a four stroke cycle diesel engine, the exhaust valve

May open and close anywhere

Opens at 30° after bottom dead centre and closes at 10° before top dead centre

Opens at bottom dead centre and closes at top dead centre

Opens at 30° before bottom dead centre and closes at 10° after top dead centre

7. In a four stroke cycle petrol engine, the compression

Starts at 40° before bottom dead centre and ends at 30° after bottom dead centre

Starts at 40° after bottom dead centre and ends at 30° before top dead centre

Starts at bottom dead centre and ends at top dead centre

May start and end anywhere

8. Pour point of fuel oil is the

Indicated by 90% distillation temperature i.e., when 90% of sample oil has distilled off

Minimum temperature to which oil is heated in order to give off inflammable vapours in sufficient quantity to ignite momentarily when brought in contact with a flame

Temperature at which it solidifies or congeals

It catches fire without external aid

9. The working pressure and temperature inside the cylinder of an internal combustion engine is _________ as compared to a steam engine.

Very low

High

Very high

Low

10. The ignition quality of petrol is expressed by

All of these

Calorific value

Octane number

Cetane number

Page 2 of 4

11. The pressure at the end of compression in the case of diesel engine is of the order of

20 kg/cm

35 kg/cm

12 kg/cm

6 kg/cm

12. The air standard efficiency of an I.C. engine is given by (where r = Compression ratio, and γ = Ratio of specific heats)

1 - (1/r^{γ - 1})

1+ r^{γ - 1}

None of these

1- r^{γ - 1}

13. Supercharging is the process of

Supplying the intake of an engine with air at a density greater than the density of the surrounding atmosphere

Supplying compressed air to remove combustion products fully

Injecting excess fuel for raising more loads

Providing forced cooling air

14. The firing order in an I.C. engine depends upon

Arrangement of the cylinders

Number of cylinders

Design of crankshaft

All of these

15. The theoretically correct air fuel ratio for petrol engine is of the order of

15: 1

6: 1

9: 1

12: 1

16. Crankcase explosion in I.C. engines usually occurs as

First a mild explosion followed by a bi explosion

Never occurs

First a big explosion followed by a mil explosion

Both mild and big explosions occurs simultaneously

17. In the opposed piston diesel engine, the combustion chamber is located

Between the pistons

There is no such criterion

Above the piston

Below the piston

18. Which of the following medium is compressed in a Diesel engine cylinder?

Fuel alone

Air and lub oil

Air and fuel

Air alone

19. In a typical medium speed 4-stroke cycle diesel engine the inlet valve

Opens at 10° after top dead center and closes 20° before the bottom dead center

Opens at top dead center and closes at bottom dead center

Opens at 20° before top dead center and closes at 35° after the bottom dead center

May open or close anywhere

20. The rating of a diesel engine, with increase in air inlet temperature, will

Decrease parabolically

Increase linearly

Decrease linearly

Increase parabolically

Page 3 of 4

21. In a typical medium speed, 4-stroke cycle diesel engine

Fuel injection starts at just before top dead center and ends just after top dead center

Fuel injection starts at top dead center and ends at 20° after top dead center

Fuel injection starts at 10° before top dead center and ends at 20° after top dead center

May start and end anywhere

22. Compression ratio of I.C. Engines is

Ratio of pressure after compression and before compression

Volume displaced by piston per stroke and clearance volume in cylinder

The ratio of volumes of air in cylinder before compression stroke and after compression stroke

Swept volume/cylinder volume

23. The probability of knocking in diesel engines is increased by

Low volatility

Higher viscosity

High self ignition temperature

All of these

24. Detonation is harmful due to

Increase in the rate of heat transfer, there is a reduction in the power output and efficiency of the engine

Excessive turbulence which removes most of the insulating gas boundary layer from the cylinder walls

High intensity of knock causes crankshaft vibration and the engine runs rough

None of the above

25. If the temperature of intake air in IC engines is lowered, then its efficiency will

Increase

Increase up to certain limit and then decrease

Decrease

Remain same

26. A stoichiometric air-fuel ratio is

Chemically correct mixture

Lean mixture

Rich mixture for over loads

Rich mixture for idling

27. Which one of the following engines will have heavier flywheel than the remaining ones?

30 kW four-stroke diesel engine running at 750 r.p.m.

30 kW two-stroke petrol engine running at 1500 r.p.m.

30 kW four-stroke petrol engine running at 1500 r.p.m.

30 kW two-stroke diesel engine running at 750 r.p.m.

28. Number of working strokes per min. for a four stroke cycle engine are _________ the speed of the engine in r.p.m.

Equal to

One-half

Four-times

Twice

29. In an internal combustion engine, the process of removing the burnt gases from the combustion chamber of the engine cylinder is known as

Detonation

Scavenging

Polymerisation

Supercharging

30. Pick up the wrong statement about supercharging

There can be limited supercharging in petrol engines because of detonation

Supercharging at high altitudes is essential

Supercharging reduces knocking in diesel engines

Supercharging results in fuel economy

Page 4 of 4

31. The operation of forcing additional air under pressure in the engine cylinder is known as

Turbulence

Scavenging

Pre-ignition

Supercharging

32. The operation of forcing additional air under pressure into the engine cylinder is known as

Delay period

Turbulence

Carburetion

Supercharging

33. The loud pulsating noise heard within the cylinder of an internal combustion engine is known as

Supercharging

Turbulence

Detonation

Pre-ignition

34. The air requirement of a petrol engine during starting compared to theoretical air required for complete combustion is

More

Less

May be more or less depending on engine capacity

Same

35. The mean effective pressure obtained from engine indicator indicates the

Instantaneous pressure at any instant

Average pressure

Maximum pressure developed

Minimum pressure

36. Which of the following is the lightest and most volatile liquid fuel?

Diesel

Kerosene

Gasoline

Fuel oil

37. If the temperature of intake air in internal combustion engine increases, then its efficiency will

Increase

Remain same

Decrease

None of these

38. Pick up the false statement

Theoretically correct mixture of air and petrol is approximately 15:1

S.I. engines are quality governed engines

Thermal efficiency of diesel engine is about 34%

High speed compression engines operate on dual combustion cycle

39. In compression ignition engines, swirl denotes a

Rotary motion of the gases in the chamber

Haphazard motion of the gases in the chamber

Radial motion of the gases in the chamber

None of the above

40. The ignition of the charge by some hot surface within the engine before the passage of spark is called

Detonation

Pre-ignition

Auto-ignition

Ignition delay

Loading...

Share this Now with Friends:

WhatsApp
Telegram
More

Related

Tags: Automobile Engineering MCQs Engineering Drawing MCQs IC engines MCQs Mechanical Engineering Refrigeration & Air-Conditioning

VideRime

A Demrot is the founder of VideRime Online Learning, a leading engineering website. He did his BE Civil and M.Tech Structure from RGPV University, Bhopal and has been working as an Assistant Professor in a reputed college.

Leave a ReplyCancel reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Ads by Google

Recent Posts

Key Benefits of Phd in any Discipline
[PDF] Basic Civil Engineering PDF by S.S. Bhavikatti
Best 20 trending Topics for final year major projects in Civil Engineering
Explain different types of road bridges through neat sketches
What are the best video editing softwares
Explain the working of marshalling yard through neat diagram
Classification of Indian Railways in detail
What do you mean by coning of wheels? Also discuss its advantages.

Membership Registration

Secured Payment

Protection

DMCA.com Protection Status

VideRime.com is the leading online Learning portal. ©2026 All Rights Reserved.

Login Now

Google

OR

* Username

*

* Password

*

Remember me

Forgot Password

Don't have account? Register Now

VideRime Registration Form

* Username

*

* Username

*

* Last Name

*

* Email Address

*

* Confirm Email Address

*

* Password

*

Strength: Very Weak

(Use Cropper to set image and
use mouse scroller for zoom image.)

Already have an account? Login