Thermodynamic Process Of The Vacuum Fask

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1. INTRODUCTION
1.1 History
In 1892, a scientist at Oxford University, Sir James Dewar has invented the “vacuum flask”. This bottle created a vacuum, which is an effective insulator. Dewar created his insulated bottle by sealing one bottle inside another and pumping out the air between them. In 1904, German glass-blower Reinhold burger and his partner Albert Aschenbrenner who patented Dewar’s invention and manufactured it for commercial use. They are the one who made bottles for Dewar. Burger and Aschenbrenner held a contest to name the “vacuum flask”. A resident of Munich submitted the name “Thermos”, which came from Greek word threm, which means hot.
Paalen, Burger, and Aschenbrenner did not register the now well-known Thermos name until
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The processes are characterized by the thermodynamic variable that is kept constant, while other variables such as temperature, pressure, volume, etc. change during the process. The processes are adiabatic process, isothermal process, isobaric process and isochoric process. Before going into the further explanation on types of thermodynamic processes, the real-life application of First Law of Thermodynamics that we choose is Thermos flask (or known as Vacuum flask).
A flask keep hot things hot or cold things cold because it does not allow heat by any three ways of heat can travel. Three ways heat can be transferred are conduction in solids, convection of fluids (either liquid or gases) and radiation through anything that allow radiation to pass.
Thermal equilibrium is an important concept in thermodynamics. When two systems are in thermal equilibrium, there is no net heat transfer between them. This occurs when the systems are at the same temperature. In other words, systems at the same temperature will be in thermal equilibrium with each
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The first law of thermodynamics then becomes:

∆U = 0 = Q – W, ∴Q = W

All the heat added to the system is used to do work. That means the isothermal compression between the double-wall in the vacuum coffee flask the work done on the gas (vacuum) goes out of the gas as heat that is lost to the surroundings. In the other words, all the heat absorbed by the gas from the liquid is converted to work in an isothermal expansion.

In isothermal process that relates to vacuum coffee flask, heat flows in and out of the gas. This can accomplished by either keeping in the gas (vacuum) between the silver surfaces that are made of a good thermal conducting material like glass or by carrying out the process very slowly.

(Heat transfer, and the first law of Thermodynamics, (n.d.)) & (

Graph on Adiabatic

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