Air-petrol ratio for maximum power generation in spark ignition engine is about_____________________?

Related Mcqs:

1. With increase in ___________________ Knocking tendency in a spark ignition petrol engine decreases?

   A. Supercharging
   B. Wall temperature
   C. Compression ratio
   D. Engine speed

2. The following heat engine produces power of 100,000 kW. The heat engine operates between 800 K and 300 K. It has a thermal efficiency equal to 50% of that of the Carnot engine for the same temperature. The rate at which heat is absorbed from the hot reservoir is____________________?

   A. 100,000 kW
   B. 160,000 kW
   C. 200,000 kW
   D. 320,000 kW

3. The efficiency of an Otto engine compared to that of a diesel engine, for the same compression ratio will be _______________?

   A. More
   B. Less
   C. Same
   D. Data insufficient to predict

4. Pure oxygen is mixed with air to produce an enriched air containing 50 volume % of oxygen. The ratio of moles of air to oxygen used is_________________?

   A. 1.72
   B. 0.58
   C. 0.5
   D. 0.2

5. Lead exhausted in the atmosphere by automobiles using leaded petrol (i.e. tetraethyl lead for improving octane number) is a lethal air pollutant which causes_________________?

   A. Paralysis of muscles & loss of appetite
   B. Nervous depression
   C. Gastritis and diarrhea
   D. All A., B. and C.

6. A car tyre of volume 0.057 m3 is inflated to 300 kPa at 300 K. After the car is driven for 10 hours, the pressure in the tyre increases to 330 kPa. Assume air is an ideal gas and Cv for air is 21 J/mole.K. The change in the internal energy of air in the tyre in J/mole is__________________?

   A. 380
   B. 630
   C. 760
   D. 880

7. Air enters an adiabatic compressor at 300K. The exit temperature for a compression ratio of 3, assuming air to be an ideal gas (Y = Cp/Cv = 7/5) and the process to be reversible, is___________________?

   A. 300 × (32/7)
   B. 300 × (33/5)
   C. 300 × (333/7)
   D. 300 × (35/7)

8. A cyclic engine exchanges heat with two reservoirs maintained at 100 and 300°C respectively. The maximum work (in J) that can be obtained from 1000 J of heat extracted from the hot reservoir is_________________?

   A. 349
   B. 651
   C. 667
   D. 1000

9. A refrigeration cycle is a reversed heat engine. Which of the following has the maximum value of the co-efficient of performance (COP) for a given refrigeration effect ?

   A. Vapor compression cycle using expansion valve
   B. Air refrigeration cycle
   C. Vapor compression cycle using expansion engine
   D. Carnot refrigeration cycle

10. Inhalation of lead compounds present in the automobile exhausts (using leaded petrol) causes________________?

    A. Blood poisoning
    B. Anaemia
    C. Nervous system disorder
    D. All A., B. and C.