Top 350+ Solved Heat Engines MCQ Questions Answer
Q. Advantage of a diesel engine over petrol engine is
a. Low fuel consumption at full load as well as part load
b. Smooth operation at all speeds
c. Low compression ratio
d. No detonation problems
e. All of the above
Q. Forced circulation of water does not take place in which of the following boiler?
a. Benson boiler
b. La Mont boiler
c. Babcock and Wilcox boiler
d. Lancashire boiler
e. Velox boiler
Q. In multistage compression, perfect intercooling means
a. Temperature of air at inlet to subsequent stages is equal to initial temperature
b. Temperature of air at inlet to subsequent stages is less than initial temperature
c. Temperature of air at inlet to subsequent stages should be zero
d. Temperature of inlet to subsequent stages should be equal to the final temperature
e. None of the above
Q. The battery used in vespa scooter is
a. No battery is used in the scooters
b. Dry-cell type
c. Lead acid type
d. Nickel-iron type
e. Nickel cadmium type
Q. Which variety of coal has low calorific value?
a. Steam coal
b. Bituminous coal
c. Lignite
d. Anthracite
e. None of the above
Q. Stoichiometric ratio is
a. Chemically correct air-fuel ratio by volume
b. Chemically correct air-fuel ratio by weight
c. Theoretical mixture of air for complete combustion
d. Actual ratio of air to fuel for maximum efficiency
e. None of the above
Q. Hot spots are
a. Defects in S.I.engines
b. Hottest point within engine cylinder
c. Do not exist in engines
d. The spots where heavier fractions of fuel are vaporised
e. The hottest spots in engines
Q. Air required for complete combustion of 1 kg of carbon is 11.6 kg. If a fuel contains 88.6% Carbon and 11.4% Hydrogen, the air requirement will
a. Will decrease
b. 12 kg
c. Will increase
d. Remain unaltered
Q. Volumetric efficiency of a well designed engine may be in the range
a. 40 to 50 percent
b. 50 to 75 percent
c. 75 to 90 percent
d. Below 40 percent
e. Below 20 percent
Q. If the boiler chimney emission consists of dense white smoke, then it can be concluded that
a. Coal contains high percentage of sulphur
b. Insufficient air has been supplied for combustion
c. Chemically correct air has been supplied for combustion
d. Excess air has been supplied for combustion
e. Coal contains high percentage of ash
Q. Compression ratio in case of gas engines waries in the range
a. 10 to 15
b. 5 to 10
c. 24 to 30
d. 20 to 24
e. 15 to 20
Q. A back pressure generally operates on pressures in the range
a. 150 - 200 kg/cm2
b. 15 - 40 kg/cm2
c. 100 - 150 kg/cm2
d. 50 - 100 kg/cm2
e. 200 - 350 kg/cm2
Q. In automobiles as the speed of vehicle increases the back pressure
a. Increases
b. Reduces
c. Remains unaffected
d. Depends on other factors
e. None of the above
Q. A mechanical indicator is used to determine
a. Pumping horse power
b. Indicated horse power
c. IHP - BHP
d. Friction horse power
e. Brake horse power
Q. During adiabatic compression
a. No heat leaves or enters the system
b. Maximum work is done
c. Specific heat remains constant
d. Temperature remains constant
e. None of the above