Mechanical Engineering Mcqs
The ultimate analysis of fuel lists _____________________?

A. Various chemical constituents, carbon, hydrogen, oxygen etc, plus ash as per-cents by volume
B. Various chemical constituents, carbon, hydrogen, oxygen, etc, plus ash as per-cents by weight
C. Fuel constituents as percents by volume of mositure, volatile, fixed carbon and ash
D. Fuel constituents as percents by weight of mositure, volatile, fixed carbon and ash

Caking coals are those which __________________________?

A. Form lumps or masses of coke
B. Burn freely
C. Show little or no fusing action
D. Burn completely

Secondary air is the used to_________________?

A. Provide air around burners for obtaining optimum combustion
B. Transport and dry the coal
C. Convert co (formed in lower zone of furnace) into c02 at higher zone
D. Air delivered by induced draft fan

Presence of moisture in fuel oil would____________________?

A. Keep the burner tips cool
B. Aid in proper combustion
C. Cause sputtering, possibly extinguish¬ing flame
D. Clean the nozzles

Water and sediment in fuel oil can be removed by _______________________?

A. Heating the oil in the settling tanks
B. Cooling the oil in the settling tanks
C. Burning the oil
D. Suspension

Primary air is the air used to__________________?

A. Provide air around burners for obtaining optimum combustion
B. Transport and dry the coal
C. Convert co (formed in lower zone of furnace) into c02 at higher zone
D. Air-delivered by forced draft fan

The economizer is used in boilers to _______________________?

A. Increase thermal efficiency of boiler
B. Economise on fuel
C. Extract heat from the exhaust flue gases
D. Increase flue gas temperature

For combustion of a fuel, following is essential_____________________?

A. Correct fuel air ratio
B. Proper ignition temperature
C. 02 to support combustion
D. All the three above

Bomb calorimeter is used to determine ___________________?

A. Higher calorific value at constant volume
B. Lower calorific value at constant volume ,
C. Higher calorific value at constant pressure
D. Lower calorific value at constant pressure