01.Thermocouples are generally used for measuring temperature:
Ans. (c) : Thermocouples are generally used for measuring temperature up to 1500oC
02. Which of the following is not a point function of the system.
Ans. (d) : Heat is path function whereas temperature, pressure and specific volume are point function.
03.The enthalpy of an ideal gas is a function of
Ans. (c) : Enthalpy is a function of temperature only.
04. 1ºC is equal to
Ans. (b) : 1ºC is equal to Kelvin, 274.15 K.
05.. Identify open system and closed system from the following
Ans. (c) : Air compressor is an open system and boiler comes under closed system (boiler having closed chamber).
06. Which thermometer is independent of the substance or material used in its construction?
Ans. (c) : Ideal gas thermometer in independent of the substance or material used in its construction.
07.The pressure of air in an automobile tyre at temperature of 27oC is 1.75 bar (gauge). Due to running the temperature of air in the rises to 87oC. What will be the gauge pressure during this running? [Patm = 1.01 bar, volume of tyre is assumed constant]
Ans. (c)= 3.4538MN-m(Compression)
08. In a steady flow reversible adiabatic process work done is equal to
Ans. (c) : In a steady flow reversible adiabatic process work done is equal to change in enthalpy.
09.Certain quantities cannot be located on the graph by a point but are given by a point but are given by the area under the curve corresponding to the process. These quantities in concepts of thermodynamics are called as
Ans. (c) : Path functions like heat transfer and work done cannot be represented by points in the graph, but can be given by the area under the curve. Heat transfer will be area under curve in T-s diagram while work done will be the area under curve in p-v diagram.
10. A steel tank placed in hot environment contains 5 kg of air at 4atm at 30°C. A portion of the air is released till the pressure becomes 2 atm. Later, the temperature of the air in the tank is found to be 150°C. The quantity of air allowed to escape is
Ans. (d)