Top 50+ Solved Fuel Air Cycles and Actual Cycles MCQ Questions Answer
Q. A perfect engine works on the Carnot cycle between 727 °C and 227°C. The efficiency of the engine is
a. 0.5
b. 0.75
c. 1
d. 0.25
Q. The air standard Otto cycle consists of
a. two constant volume and two isentropic processes
b. two constant pressure and two isentropic processes
c. two constant pressure and two constant volume processes
d. none of the above
Q. Mean effective pressure of Otto cycle is
a. inversely proportional to pressure ratio
b. directly proportional to pressure ratio
c. does not depend on pressure ratio
d. proportional to square root of pressure ratio
Q. For a given compression ratio the work output of Otto cycle is
a. increases with Increase in r
b. decreases with increase in r
c. is not affected
d. none of the above
Q. For a given value of r, efficiency of Otto cycle
a. decreases with compression ratio
b. increases with compression ratio
c. is not affected
d. none of the above
Q. For dual combustion cycle for fixed value of heat addition and compression ratio
a. mep wil be greater with increase in rp, and decrease in rc
b. mep will be greater with decrease in rp and decrease in rc
c. mep remain the same with increase in rp and decrease in rc
d. none of the above
Q. The normal range of, compression ratio for Otto cycle is
a. 6 to 10
b. 2 to 4
c. >10
d. none of the above
Q. The actual efficiency of a good engine is about _______of the estimated fuel-air cycleefficiency.
a. 100%
b. 85%
c. 50%
d. 25%
Q. With dissociation peak temperature is obtained
a. at the stoichiometric air-fuel ratio
b. when the mixture is slightly lean
c. when the mixture is slightly rich
d. none of the above
Q. With dissociation the exhaust gas temperature
a. decreases
b. increases
c. no effect
d. increases upto certain air-fuel ratio and then decreases
Q. Fuel-air ratio affects maximum power output of the engine due to
a. higher specific heats
b. chemical equilibrium losses
c. both (a) and (b)
d. none of the above
Q. Mean effective pressure at a given compression ratio is maximum when the air-fuel ratio is
a. higher than stoichiometric
b. lower than stoichiometric
c. equal to stoichionetric
d. none of the above
Q. For a compressor process with variable specific heat the peak temperature and pressure are_______compared to constant specific heat
a. lower
b. higher
c. no effect
d. none of the above