In a typical medium speed 4-stroke cycle diesel engine________________?

Related Mcqs:

1. In a typical medium speed, 4-stroke cycle diesel engine ___________________?

   A. fuelinjection starts at 10° before to dead center and ends at 20° after tor dead center
   B. fuel injection starts at top dead center and ends at 20° after top dead center
   C. fuel injection starts at just before top dead center and ends just after top deac center
   D. may start and end anywhere
   E. none of the above

2. In a typical medium speed 4-stroke cycle diesel engine the inlet valve_____________________?

   A. opens at 20° before top dead center and closes at 35° after the bottom dead center
   B. opens at top dead center and closes at bottom dead center
   C. opens at 10° after top dead center and closes 20° before the bottom dead center
   D. may open or close anywhere
   E. remains open for 200°.

3. In a typical medium speed 4 stroke cycle diesel engine_______________?

   A. exhaust valve opens at 35° before bot-tom dead center and closes at 20° after top dead center
   B. exhaust valve opens at bottom ‘dead center and closes at top dead center
   C. exhaust valve opens just after bottom dead center and closes just before top dead center
   D. may open and close anywhere
   E. none of the above is true

4. For same power and same speed, the flywheel of a four stroke engine as compared to two-stroke I.C. engine will be________________?

   A. smaller
   B. bigger
   C. same size
   D. dependent on other engine parameters
   E. unpredictable

5. In precombustion chamber in diesel engine________________?

   A. The shape and layout of the pistion crown, the inlet port, and the valve produce the turbulent effect of fuel mixture
   B. Fuel is injected into an auxiliary chamber that is separated from the cylinder by an orifice or throat
   C. Only a part of air charge is contained in an auxiliary chamber in which the fuel starts to burn with insufficient air which due to explosion tendency mixes thoroughly into main cylinder charge
   D. There are no valves

6. 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.

7. For the same size and weight, a two stroke engine as compared to four stroke engine will generate power_________________?

   A. about twice
   B. about 0.5 times
   C. nearly equal
   D. about 1.7 times
   E. about 5 times

8. 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

9. 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

10. A 4-stroke diesel engine needs about following amount of air_________________?

    A. 75 cc per min. per h.p.
    B. 750 cc per min. per h.p.
    C. 7500 cc per min. per h.p.
    D. 75000 cc per min. per h.p.
    E. 750000 cc per min. per h.p