Mechanical IC Engines MCQ Part 4

Attempt Free Mechanical IC Engines MCQ Part 4 Here. Read The Important Mechanical MCQ From Below.

Q1. In a typical medium speed 4-stroke cycle diesel engine the inlet valve
A. opens at 20° before top dead center and closes at 35° after the bottom dead center
B. opens at top dead center and closes at bottom dead center
C. opens at 10° after top dead center and closes 20° before the bottom dead center
D. may open or close anywhere
E. remains open for 200°.

Answer : A

Q2. The mean effective pressure obtained from engine indicator indicates the.
A. maximum pressure developed
B. minimum pressure
C. instantaneous pressure at any instant
D. average pressure

Answer : D

Mechanical IC Engines MCQ Part 4

Q3. The pressure and temperature at the end of compression stroke in a petrol engine are of the order of
A. 4 – 6 kg/cm2 and 200 – 250°C
B. 6 – 12 kg/cm2 and 250 – 350°C
C. 12 – 20 kg/cm2 and 350 – 450°C
D. 20 – 30 kg/cm2 and 450 – 500°C
E. 30 – 40 kg/cm2 and 500 – 700°C.

Answer : B

Q4. The following volume of air is required for consuming 1 liter of fuel by a four stroke engine.
A. 1 m3
B. 5 m3
C. 5-6 m3
D. 9-10 m3

Answer : D

Q5. The pressure at the end of compression in the case of diesel engine is of the order of
A. 6 kg/cm
B. 12kg/cmz
C. 20 kg/cmz
D. 27.5 kg/cmz
E. 35 kg/cm

Answer : E

Mechanical IC Engines MCQ Part 4

Q6. Which is more viscous lib oil.
A. SEA 30
B. SAE 40
C. SAE 50
D. SAE 80

Answer : D

Q7. The maximum temperature in the I.C. engine cylinder is of the order of
A. 500- 1000°C
B. 1000- 1500°C
C. 1500-2000°C
D. 2000-2500°C
E. 2500-3000°C

Answer : D

Q8. The thermal efficiency of a diesel cycle having fixed compression ratio, with increase in cut-off ratio will
A. increase
B. decrease
C. be independent
D. may increase or decrease depending on other factors
E. none of the above.

Answer : B

Mechanical IC Engines MCQ Part 4

Q9. Pick up the wrong statement
A. 2-stroke engine can run in any direction
B. In 4-stroke engine, a power stroke is obtained in 4-strokes
C. thermal efficiency of 4-strokc engine is more due to positive scavenging
D. petrol engines work on to cycle
E. petrol engines occupy more space than diesel engines for same power output.

Answer : E

Q10. Combustion in compression ignition engines is
A. homogeneous
B. heterogeneous
C. both (a) and (b)
D. laminar
E. turbulent.

Answer : B

Mechanical IC Engines MCQ Part 4

Q11. The fuel in diesel engine is normally injected at pressure of
A. 5-10 kg/cm2
B. 20-25 kg/cm2
C. 60-80 kg/cm2
D. 90-130 kg/cm2
E. 150-250 kg/cm2

Answer : D

Q12. The specific fuel consumption per BHP hour for diesel engine is approximately
A. 0.15 kg
B. 0.2 kg
C. 0.25 kg
D. 0.3 kg
E. 0.35 kg.

Answer : B

Mechanical IC Engines MCQ Part 4

Q13. The temperature of interior surface of cylinder wall in normal operation is not allowed to exceed
A. 80°C
B. 120°C
C. 180°C
D. 240°C
E. 320°C.

Answer : C

Q14. Crankcase explosion in I.C. engines usually occurs as
A. first a mild explosion followed by a bi explosion
B. first a big explosion followed by a mil explosion
C. both mild and big explosions occi simultaneously
D. never occurs
E. unpredictable.

Answer : A

Mechanical IC Engines MCQ Part 4

Q15. Compression loss in I.C engines occurs duto
A. leaking piston rings
B. use of thick head gasket
C. clogged air-inlet slots
D. increase in clearance volume caused b bearing-bushing wear
E. all of the above.

Answer : E