A steam carrying pipeline is insulated with two layers of insulating materials with the inferior insulation material forming the inner part. If the two insulating layers are interchanged, the heat conducted will____________________?

Related Mcqs:

1. A solid metallic block weighing 5 kg has an initial temperature of 500°C. 40 kg of water initially at 25°C is contained in a perfectly insulated tank. The metallic block is brought into contact with water. Both of them come to equilibrium. Specific heat of block material is 0.4 kJ.kg-1. K-1. Ignoring the effect of expansion and contraction and also the heat capacity to tank, the total entropy change in kJ.kg-1, K-1 is_________________?

   A. -1.87
   B. 0
   C. 1.26
   D. 3.91

2. High pressure steam is expanded adiabatically and reversibly through a well insulated turbine, which produces some shaft work. If the enthalpy change and entropy change across the turbine are represented by ΔH and ΔS respectively for this process ?

   A. Δ H = 0 and ΔS = 0
   B. Δ H ≠ 0 and ΔS = 0
   C. Δ H ≠ 0 and ΔS ≠ 0
   D. Δ H = 0 and ΔS ≠ 0

3. A perfectly insulated container of volume V is divided into two equal halves by a partition. One side is under vacuum, while the other side has one mole of an ideal gas (with constant heat capacity) at 298 K. If the partition is broken, the final temperature of the gas in the container___________________?

   A. Will be greater than 298 K
   B. Will be 298 K
   C. Will be less than 298 K
   D. Cannot be determined

4. Critical temperature is defined as the temperature above which a gas will____________________?

   A. Not liquify (barring exceptions)
   B. Immediately liquify
   C. Never liquify however high the pressure may be
   D. None of these

5. On opening the door of an operating refrigerator kept in a closed room, the temperature of the room will____________________?

   A. Increase
   B. Decrease
   C. Remain same
   D. Increase in summer and will decrease in winter

6. Dryness factor of steam is defined as the ratio of the mass of vapor in the mixture to the mass of the mixture. Dryness factor of steam is measured by a _______________ calorimeter ?

   A. Bomb
   B. Throttling
   C. Junker’s
   D. Boy’s

7. Which of the following identities can be most easily used to verify steam table data for superheated steam ?

   A. (∂T/∂V)S = (∂p/∂S)V
   B. (∂T/∂P)S = (∂V/∂S)P
   C. (∂P/∂T)V = (∂S/∂V)T
   D. (∂V/∂T)P = -(∂S/∂P)T

8. Dryness fraction of wet steam is defined as the ratio of mass of vapour in the mixture to the mass of mixture ______________ calorimeter is not used for measuring the dryness fraction of steam?

   A. Bomb
   B. Separating
   C. Bucket
   D. Throttling

9. Steam undergoes isentropic expansion in a turbine from 5000 kPa and 400°C (entropy = 6.65 kJ/kg K) to 150 kPa) (entropy of saturated liquid = 1.4336 kJ/kg. K, entropy of saturated vapour = 7.2234 kJ/kg. K) The exit condition of steam is_______________?

   A. Superheated vapour
   B. Partially condensed vapour with quality of 0.9
   C. Saturated vapour
   D. Partially condensed vapour with quality of 0.1

10. 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