If the compression ratio of an engine working on Otto cycle is increased from 5 to 7, the %age increase in efficiency will be________________?

Related Mcqs:

1. The air standard efficiency of an Otto cycle compared to diesel cycle for the given compression ratio is__________________?

   A. same
   B. less
   C. more
   D. more or less depending on power rating
   E. unpredictable

2. The efficiency of the ideal diesel cycle is ________ than that of Otto cycle, for the same compression ratio

   A. Higher
   B. Lower
   C. Equal
   D. None of these

   Submitted by: Faheem Zaman Dhaunroo

3. The thermal efficiency of a semi-diesel cycle having fixed compression ratio and fixed quantity of heat, with increase in pressure ratio will_______________?

   A. increase
   B. decrease
   C. remain unaffected
   D. increase/decrease depending upon engine capacity
   E. first increase and then decrease

4. The thermal efficiency of a two cycle engine as compared to four cycle engine is_________________?

   A. more
   B. less
   C. same
   D. more upto some load and then less
   E. it may be less or more depending on several other factors

5. The thermal efficiecny of a diesel cycle having fixed compression ratio, with increase in cut-off ratio will___________________?

   A. increase
   B. decrease
   C. be independent
   D. may increase or decrease depending on other factors
   E. none of the above

6. 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

7. 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

8. 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

9. 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.

10. In diesel engine, the compression ratio in comparison to expansion ratio is_______________?

    A. same
    B. less
    C. more
    D. variable
    E. more/less depending on engine capacity.