Heat release during phase change is observed in case of a/an_________________?

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. Parallel straight line pattern of temperature distribution for both hot and cold fluids is observed in case of heat exchanger of the type________________?

   A. Parallel flow with equal heat capacities
   B. Counter flow with equal heat capacities
   C. Counter flow with unequal heat capacities
   D. Parallel flow with unequal heat capacities

3. Spark plug is provided in a/an_________________?

   A. Engine having carburettor
   B. Diesel engine
   C. Compression ignition engine
   D. Both B. & C.

4. The efficiency of a Carnot heat engine operating between absolute temperatures T1 and T2 (when, T1 > T2) is given by (T1 – T2)/T1. The co-efficient of performance (CO.P.) of a Carnot heat pump operating between T1 and T2 is given by_________________?

   A. T1/(T1-T2)
   B. T2/(T1-T2)
   C. T1/T2
   D. T2/T1

5. In a counter flow heat exchanger, hot fluid enters at 170°C & leaves at 150°C, while the cold fluid enters at 50°C & leaves at 70°C. The arithmetic mean temperature difference in this case is ______________ °C?

   A. 20
   B. 60
   C. 120
   D. ∞

6. Out of the following, maximum temperature drop for a given heat flow & for the same thickness will be in the case of________________?

   A. Steel
   B. Glass wood
   C. Copper
   D. Fireclay bricks

7. Heat transfer by ______________ is almost absent in case of fluidised bed drying operation?

   A. Radiation
   B. Conduction
   C. Convection
   D. Both B. & C.

8. A reduction in thermal resistance during heat transfer does not occur in the___________________?

   A. Convection heat transfer by stirring the fluid and cleaning the heating surface
   B. Conduction heat transfer by reduction in the material thickness and increase in the thermal
   conductivity
   C. Radiation heat transfer by increasing the temperature and reducing the emissivity
   D. None of these

9. Transformation range for ferrous material is the temperature interval during which ___________________ is formed during its heating?

   A. Cementite
   B. Austenite
   C. Martensite
   D. Pearlite

10. Cementite is in the lamellar form in the _____________________ phase of steel ?

    A. Martenistic
    B. Bainitic
    C. Pearlitic
    D. Ferritic