Primary air is the air used to__________________?

Related Mcqs:

1. If partial pressure of air and steam be pa and ps respectively in a condenser, then according to Dalton’s law, the pressure in condenser is equal to__________________?

   A. Ps-Pa
   B. pa-ps
   C. Pa+P
   D. non of these

2. Tertiary air is the air used to____________________?

   A. provide air around burners for obtaining optimum combustion
   B. transport and dry the coal
   C. cool the scanners
   D. supply air for ignitors
   E. convert CO (formed in lower zone of furnace) into C02 at higher zone

3. The change in internal energy in steam engines equals to__________________?

   A. work done during the rankine cycle ;
   B. work done during compression.
   C. work done during adiabatic expansion
   D. change in enthalpy
   E. none of the above

4. Feed water conditioning in thermal power plants in done to__________________?

   A. reduce hardness and for removal of solids
   B. increase efficiency-of thermal power plant
   C. increase *heat transfer rate
   D. increase steam parameters
   E. all of the above

5. Free air is the air at________________?

   A. atmospheric conditions at any specific location
   B. 20°C and 1 kg/cm2 and relative humidity of 36%
   C. 0°C and standard atmospheric conditions
   D. 15°C and 1 kg/cm2
   E. 25°C, 1 kg/cm2 and relative humidity of 50%.

6. Standard air is the air at_____________________?

   A. atmospheric conditions at any specific location
   B. 20°C and 1 kg/cm2 and relative humidity 36%
   C. 0°C and standard atmospheric conditions
   D. 15°C and 1 kg/cm2
   E. 25°C, 1 kg/cm2 and RH of 60%.

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 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

10. What is the weight (in lbf) of one gallon of air at 1 atm and 25˚C? The molecular mass of air is 28.97 g/mole = 0.02897 kg/mole

    A. 90 lbf
    B. 65.78 lbf
    C. 0.00989 lbf
    D. 3.00989 lbf

    Submitted by: Faheem Zaman Dhaunroo