The theoretically correct mixture of air and petrol is approximately ________________?

Related Mcqs:

1. 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

2. The thermal efficiency of a petrol engine of two stroke with crank case scavenging as compared to four stroke petrol engine with same comperssion ratio will be_____________________?

   A. higher
   B. lower
   C. same
   D. depends on size of engine
   E. unpredictable.

3. 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

4. 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

5. 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

6. 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

7. Theoretically, the following engine should have maximum efficiency________________?

   A. gas engine
   B. 2-stroke S.I. engine
   C. 4-stroke S.I. engine
   D. steam engine
   E. 4-stroke C.I. engine

8. While steam expands in turbines, theoretically the entropy________________?

   A. remains constant
   B. increases
   C. decreases
   D. behaves unpredictably
   E. none of the above

9. 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

10. Air fuel ratio for idling speed of a petrol engine is approximately_________________?

    A. 1 : 1
    B. 5 : 1
    C. 10:1
    D. 15 : 1
    E. 20 : 1