For a spontaneous natural process at constant temperature and pressure, the free energy of the system always____________________?

Related Mcqs:

1. ______________________ temperature remains constant during adiabatic saturation process of unsaturated air ?

   A. Dew point
   B. Dry bulb
   C. Wet bulb
   D. None of these

2. Brass parts with high residual tensile stress at the surface are susceptible to season cracking (i.e. spontaneous cracking occuring on exposure to atmospheric corrosion), if its zinc percentage is more than ?

   A. 5
   B. 10
   C. 20
   D. 35

3. The boiling & freezing points on a newly defined temperature scale in degree ‘D’ are 400°D & 100°D respectively. The temperature reading corresponding to 60°C on this new temperature scale will be equal to _____________ °D ?

   A. 140
   B. 180
   C. 240
   D. 280

4. Heating the Hypo-eutectoid steels to 30°C above the upper critical temperature line, soaking at that temperature and then cooling slowly to the room temperature to form a pearlite & ferrite structure is called_______________________?

   A. Tempering
   B. Hardening
   C. Annealing
   D. Normalising

5. The ratio of thermal & electrical conductivity is same for all the metals at the same temperature; and at around room temperature, this ratio is proportional to(where, T = absolute temperature, °K) ?

   A. T
   B. 1/T
   C. T2
   D. 1/T2

6. High relative humidity decreases the evaporative process and as the temperature is increased, the relative humidity decreases. The comfort range for human body is the ambient temperature of 22 to 27°C with relative humidity ranging from _______________ percent ?

   A. 5 to 10
   B. 15 to 25
   C. 45 to 50
   D. 75 to 80

7. Direct conversion of thermal energy to electrical energy is facilitated by the____________________?

   A. Fuel cells
   B. Photo voltaic cell
   C. Magneto hydrodynamic generator
   D. None of these

8. A thin, flat & square plate measuring 2 m × 2 m is freely hanging in ambient air at 25°C. It is exposed to the solar radiation falling on one side of the plate at the rate of 500 W/m2. The plate temperature will remain constant at 30°C, if the convective heat transfer co-efficient is ________________ W/m2 °C ?

   A. 50
   B. 100
   C. 150
   D. 200

9. Midrex process of sponge iron production uses reformed natural gas as the reducing agent, which uses iron ore in the form of_________________?

   A. Lumps
   B. Pellets
   C. Briquettes
   D. Sinter

10. Which of the following varies as the square root of oil pressure during atomisation of fuel oil through a pressure jet burner ?

    A. Output & fineness
    B. Velocity
    C. Both A. & B.
    D. None of these