Heat Transfer, Refrigeration and Air Conditioning Questions

• The horizontal and non-uniformly spaced lines on a psychrometric chart indicates
• In order to cool and dehumidify a stream of moist air, it must be passed over the coil at a temperature
• Which of the following refrigerant is highly toxic and flammable?
• The most commonly used method for the design of duct size is the
• The undesireable property of a refrigerant is
• The expression Q = ρ AT4 is called
• In actual air-conditioning applications for R-12 and R-22, and operating at a condenser temperature of 40° C and an evaporator temperature of 5° C, the heat rejection factor is about
• The heating of air, without any change in its specific humidity, is known as sensible heating.
• In counter-current flow heat exchangers
• In a refrigeration system, the expansion device is connected between the
• During sensible cooling of air, specific humidity
• Thermal conductivity of solid metals __________ with rise in temperature.
• An evaporator is also known as
• Stefan-Boltzmann law is applicable for heat transfer by convection.
• The unit of Stefan-Boltzmann constant is
• The coefficient of performance (C.O.P.) is the reciprocal of the efficiency of a heat engine.
• The ratio of the energy absorbed by the body to the total energy falling on it, is called
• The emissive power of a body depends upon its
• When tc1 and tc2 are the temperatures of cold fluid at entry and exit respectively and th1 and th2 are the temperatures of hot fluid at entry and exit point, and cold fluid has lower heat capacity rate as compared to hot fluid, then effectiveness of the heat exchanger is given by
• In a psychrometric chart, specific humidity (moisture content) lines are