A. lean mixture has high reaction time
B. rich mixture has high reaction time
C. chemically correct mixture has mini-mum reaction time
D. all of the above
E. non of the above
Related Mcqs:
- The specific fuel consumption for a petrol engine first decreases with increase in fuel air ratio and then increases with further increase in fuel air ratio. The minimum value occurs in the range of__________________?
A. lean mixture
B. chemically correct mixture
C. rich mixture
D. unpredictable
E. none of the above - Auto-ignition reaction time for petrol engine first decreases with increase in fuel air ratio, reaches a minimum value and then increases with subsequent increase in fuel air ratio. The minimum value occurs in the region of________________?
A. Lean mixture
B. Chemically correct fuel air ratio
C. Rich mixture
D. Unpredictable - The m.e.p. of a petrol engine first increases as the fuel air ratio is increased and then decreases on further increase in fuel air ratio. The M.E.P is maximum in the zone of________________?
A. lean mixture
B. chemically correct mixture
C. rich mixture
D. unpredictable
E. none of the above - Heating value of fuel used is as on fired basis. If it is reported for dry or moisture free fuel, then latter should be multiplied by the following factor to correct for as fired value ___________________?
A. (1- moisture content)
B. (1 + moisture content)
C. 1 + moisture content
D. 1 – moisture content - The theoretically correct air fuel ratio for petrol engine is of the order of___________________?
A. 6 : 1
B. 9 : 1
C. 12 : 1
D. 15 : 1
E. 20 : 1 - The fuel air ratio in a petrol engine fitted with suction carburettor, operating with dirty air filter as compared to clean filter will be________________?
A. higher
B. lower
C. remain unaffected
D. unpredictable
E. none of the above - Which is not correct statement about pulverised fuel firing ?
A. high burning rate is possible
B. heat release can be easily controlled
C. fuel burns economically
D. it is the best technique for burning high ash content fuel having low fusion ash
E. separate mills are required to powder the coal - Which is not correct statement about effect of sulphur in fuel ___________________?
A. it has heating value
B. it helps in electrostatic precipitation of ash in flue-gases
C. it leads to corrosion of air heaters, ducting, etc. if flue gas exit temperature is low
D. it erodes furnace walls
E. none of the above - To reduce the possibility of knock in the C.I. engines, the first elements of fuel and air should have_______________?
A. high temperature
B. high density
C. short delay
D. reactive mixture
E. all of the above - In petrol engines, the maximum power is developed corresponding to relative fuel air ratio of________________?
A. 0.85
B. 1
C. 1.1 to 1.3
D. 1.2 to 1.5
