What is the formula for refrigerator?
For a refrigerator the coefficient of performance is COP = Qlow/(-W). Details of the calculation: (a) COP = Qlow/(-W). (-W) = Qlow/COP = 120/5 J = 24 J.
Which law of thermodynamics is used in refrigerator?
the second law of thermodynamics
According to the second law of thermodynamics: “It is impossible for a self-acting machine unless energy is provided by any external agency, to transfer heat from a body having lower temperature to another at a higher temperature”. This is the basic principle used for the working of a refrigerator.
How is thermodynamics used in refrigerator?
According to the Second Law of Thermodynamics, heat will always flow spontaneously from hot to cold, and never the other way around. A refrigerator causes heat to flow from cold to hot by inputting work, which cools the space inside the refrigerator.
What is the cop of refrigerator?
The coefficient of performance, COP, of a refrigerator is defined as the heat removed from the cold reservoir Qcold (i.e., inside a refrigerator) divided by the work W done to remove the heat (i.e., the work done by the compressor).
How do you calculate refrigerant tons?
Some commercial and industrial refrigeration systems are rated in Tons of Refrigeration (TR, tons). A ton is the amount of heat removed by an air conditioning system that would melt 1 ton (2000 lbs.)…Converting between Btu/h and Tons of Refrigeration.
Btu/h | Refrigeration Ton | kW |
---|---|---|
48000 | 4 | 14.1 |
54000 | 4 1/2 | 15.8 |
60000 | 5 | 17.6 |
What is a good energy rating for a refrigerator?
Note that the Most Efficient list includes fridges that have an estimated annual energy use ranging from 151 to 576 kwH.
What is COP in thermodynamics?
COP (Coefficient of Performance) The Co-efficient of performance (COP) is an expression of the efficiency of a heat pump. When calculating the COP for a heat pump, the heat output from the condenser (Q) is compared to the power supplied to the compressor (W).
What is a perfect refrigerator?
The U.S. Food and Drug Administration (FDA) says the recommended refrigerator temperature is below 40°F; the ideal freezer temp is below 0°F. However, the ideal refrigerator temperature is actually lower: Aim to stay between 35° and 38°F (or 1.7 to 3.3°C). Temperatures above the 35° to 38°F zone may be too high.
How does a refrigerator work physics?
Refrigerators work by causing the refrigerant circulating inside them to change from a liquid into a gas. This process, called evaporation, cools the surrounding area and produces the desired effect. When you release the contents into the lower pressure open space, it turns from a liquid to a gas.
What is ideal refrigeration cycle?
In an ideal vapor-compression refrigeration cycle, the refrigerant enters the compressor as a saturated vapor and is cooled to the saturated liquid state in the condenser. It is then throttled to the evaporator pressure and vaporizes as it absorbs heat from the refrigerated space.
How does the four 4 laws of thermodynamics apply its rules to a refrigerator when a hot soup is placed inside it?
How does the four (4) Laws of Thermodynamics apply its rules to a refrigerator when a hot soup is placed inside it? The application of the laws of thermodynamics to a refrigerator when a hot soup is placed inside it is the same as to a refrigerator without a hot soup.