How does the Second Law of Thermodynamics help in the working of a refrigerator?
Asked by Topperlearning User | 17th Apr, 2015, 02:29: PM
A way of stating the second law of thermodynamics is that work must be done to get heat to flow from a cold object to a hot object. In a refrigerator, there is a cycle that is carried on continuously. A liquid refrigerant substance vaporizes in the cooling coils inside the fridge. The fluid absorbs heat from its surroundings to vaporize. This cools the interior of the fridge. The gas thus formed is pumped to the exterior of the fridge where it is compressed into a liquid. Work is done on the gas to compress the gas, causing the gas to release heat. This heat is lost to the air surrounding the fridge. Hence, heat is moved from the inside of the fridge to the outside.
Answered by | 17th Apr, 2015, 04:29: PM
- State second law of thermodynamics. Distinguish between heat engine and refrigerator
- State the second law of thermodynamics in terms of entropy.
- State a few statements for second law of thermodynamics.
- State two conditions of a reversible process. What is a quasi-static process?
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- State whether the following processes are reversible or irreversible : (i) Heat production by friction (ii) The growth of a planet (iii) Diffusion of gases (iv) Electrolysis (v) Sudden unbalanced expansion of a gas (vi) Carnot's cycle (vii) Joule's heating in an electrical resistance.
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