MCQ
2181. During a refrigeration cycle heat is rejected by the refrigerant in a-
compressor
condenser
evaporator
expansion valve
2182. Intensive property of a system is one whose value-
Depends on the mass of the system, like volume
Does not depend on the mass of the system, like temperature, pressure etc.
Is not dependent on the path followed but on the state
Is dependent on the path followed and not on the state
2183. A refrigerant with the highest critical pressure is-
R-11
R-22
R-12
Ammonia
2184. The ratio of two specific heats of air is equal to-
0.17
0.24
0.1
1.41
2185. Superheated vapour behaves—
Exactly as gas
As steam
As ordinary vapour
Approximately as a gas
2186. The capacity of a domestic refrigerator is the range of-
0.1 to 0.3 TR
1 to 3 TR
3 to 5 TR
5 to 7 TR
2187. According to kinetic theory of gases, the absolute zero temperature is attained when-
Volume of the gas is zero
Pressure of the gas is zero
Kinetic energy of the molecules is zero
Specific heat of gas is zero
2188. According to Kelvin-Planck statement, it is impossible to construct a device operating on a cycle which transfers heat from-
Low pressure heat reservoir to high pressure reservoir
Low temperature heat reservoir to high temperature reservoir
High pressure heat reservoir to low pressure reservoir
High temperature heat reservoir to low temperature reservoir
2189. Specific heat of air at constant pressure is equal to-
0.17
0.21
0.24
1.0
2190. A domestic refrigerator has the co- efficient of performance-.
equal to 10
less than 10
more than 10
none
2191. Temperature of a gas is produced due to-
Its heating value
Kinetic energy of molecules
Repulsion of molecules
Attraction of molecules
2192. Zeroth law of thermodynamics-
Deals with conversion of mass and energy
Deals with reversibility and irreversibility of process
States that if two systems are both in equilibrium with a third system, they are in thermal equilibrium with each other
Deals with heat engines
2193. A standard ice point temperature corresponds to the temperature of-.
water at 0°C
ice at-4°C
solid and dry ice
mixture of ice and water under equilibrium conditions
2194. Which of the following refrigerant has the lowest freezing point?
R-11
R-22
R-12
Ammoma
2195. Which of the following variables controls the physical properties of a perfect gas?
Pressure
Temperature
Volume
All of the above
2196. Kelvin-Planck's law deals with-
Conservation of heat
Conservation of work
Conversion of heat into work
Conversion fo work into heat
2197. A condenser of refrigeration system rejects heat at the rate of 120kW while its compressor consunes a power of 30 kW. The coefficient of performance of the system would be-
1/4
3
4
1/3
2198. In an isothermal process-
There is no change in enthalpy
There is no change in internal energy
There is no change in temperature
All of these
2199. Measurement of temperaturę is based on-
Thermodynamic properties
Zeroth law of thermodynamics
First law of thermodynamics
Second law of thermodynamics
2200. Which of the following refrigerant is highly toxic and flammable?
sulphur dioxide
Freon-12
Ammonia
Carbon dioxide