In case of compression of one kg of air, the work done will be the least, when the value of polytropic index ‘n’ is______________________?

Related Mcqs:

1. Work required for compression of a gas contained in a cylinder is 7000 kJ. During compression, heat interaction of 3000 kJ causes the surroundings to be heated. Internal energy change of the gas during the compression is __________________ kJ ?

   A. +4000
   B. -4000
   C. 10000
   D. -10000

2. Multistage compression of air as compared to single stage compression offers the advantage of______________?

   A. Power saving per unit weight of air delivered
   B. Moisture elimination in the inter-stage cooler
   C. Increased volumetric efficiency
   D. All A , B. & C.

3. In practice, the compression ratio of compression-ignition (CI) engine ranges from ______________________?

   A. 15 to 25
   B. 5 to 10
   C. 40 to 55
   D. 60 to 70

4. With increase in compression ratio, the volumetric efficiency of air compressor____________________?

   A. Increases
   B. Decreases
   C. Remain same
   D. May increase or decrease (depends on the suction pressure)

5. The ratio of the shear stress to the principal stress on a principal plane is______________________?

   A. 0
   B. 1
   C. 1/2
   D. 1/3

6. Case hardening is not done by________________?

   A. Nitriding
   B. Hot dipping
   C. Electroplating
   D. Both ‘B’ & ‘C’

7. Work done by a/an _________________ process is determined by ∫p. dv ?

   A. Adiabatic
   B. Quasi-static
   C. Isothermal
   D. Isentropic

8. Which of the following materials has the least scrap value ?

   A. Aluminium
   B. Stainless steel
   C. Brass
   D. Copper

9. Which of the following has the least value of ultimate tensile strength (UTS) ?

   A. Medium carbon steel
   B. High carbon steel
   C. Cast iron
   D. Wrought iron

10. Which of the following has the highest value of refractive index ?

    A. Brine (sea water)
    B. Diamond
    C. Distilled water
    D. Glass