Here are top 20 important MCQs of IC ENGINE . Read the questions carefully and try to answer all of them from your own.
Q1. In a four stroke engine, the working cycle is completed in
a) one revolution of crankshaft
b) two revolution of crankshaft
c) three revolution of crankshaft
d) four revolution of crankshaft
Q2. A two stroke cycle engine gives ___ numbers of power strokes as compared to the four stroke cycle engine, at the same engine speed
a) half
b) same
c) double
d) four times
Q3. Theoretically, a four stroke cycle engine should develop ___ power as that as that of a two stroke cycle engine
a) half
b) same
c) double
d) four times
Q4. Thermal efficiency of a two stroke cycle engine is ___ a four stroke cycle engine
a) equal to
b) less than
c) more than
d) can’t be calculated
Q5. The thermodynamic cycle on which the petrol engine works, is
a) Otto cycle
b) Joule cycle
c) Rankine cycle
d) Stirling cycle
Q6. The theoretically Correct mixture of air and fuel is
a) 10:1
b) 15:1
c) 20:1
d) 25:1
Q7. The inlet valve of a four stroke cycle internal combustion engine remains open for
a) 130°
b) 180°
c) 230°
d) 270°
Q8. In a four stroke cycle, the minimum temperature inside the engine cylinder occurs at the
a) begining of the suction stroke
b) end of suction stroke
c) beginning of exhaust stroketo
d) end of exhaust stroke
Q9. During idling, a petrol engine requires __ mixture
a) lean
b) rich
c) chemically correct
d) none of these
Q10. In a petrol engine, the mixture has the lowest pressure at the
a) beginning of suction stroke
b) end of suction stroke
c) end of compression stroke
d) none of these
Q11. In a petrol engine, if diesel is used then the engine will
a) not run
b) run more efficiently
c) run at high speed
d) explode
Q12. A diesel engine has
a) one valve
b) two valves
c) three valves
d) four valves
Q13. The object of providing masked inlet valve in the air passage of compression ignition engines is to
a) enhance flow rate
b) control air flow
c) induce primary swirl
d) induce secondary turbulence
Q14. If the temperature of intake air in internal combustion engine increases, then its efficiency will
a) remain same
b) decrease
c) increase
d) no relation with temperature
Q15. If petrol is used in a diesel engine, then
a) lower power will be produced
b) efficiency will be low
c) higher knocking Will occur
d) black smoke will be produced
Q16. A petrol engine, during suction stroke draws
a) air only
b) petrol only
c) a mixture of petrol and air
Q17. A diesel engine, during suction stroke, draws
a) air only
b) diesel only
c) a mixture of diesel and air
Q18. The colour of exhaust from diesel engine is generally
a) white
b) bluish
c) black
d) violent
Q19. The pressure at the end of compression, in petrol engines, is approximately
a) 10 bar
b) 20 bar
c) 25 bar
d) 35 bar
Q20. The pressure at the end of the compression, in diesel engines, is approximately
a) 10 bar
b) 20 bar
c) 25 bar
d) 35 bar
That was the set 1 of top important MCQs of Internal combustion engine. This will help a lot for the competitive examinations. If you like this content then do share this with your well wishers. If you have any doubts regarding any mechanical engineering then let us know in comment section or contact us through email.