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# PV diagrams - part 2: Isothermal, isometric, adiabatic processes

There are three types of thermodynamic processes you should know: isothermal, isometric, and adiabatic. An isothermal process is all about keeping the temperature constant, while an isometric process maintains a constant volume. The trickiest of the three is the adiabatic process, where no heat is exchanged and changes in volume can alter both pressure and temperature. Created by David SantoPietro.

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• Why is an adiabat steeper than an isotherm??
In the case of an adiabatic process the molecules move faster (on average) than in the case of an isothermal process and thus the pressure is higher (steeper curve)....
• How does the pressure get decreased in Isothermal Expansion? I know that PV=Constant but I want to know what actually happen inside the system due to which internal energy remains constant and pressure get decreased .
• Gas pressure comes from the impact of gas molecules against the inner walls of the container. This pressure depends on the speed of the molecules and the number of impacts per square inch of the internal surface . The speed does not change because the temperature is constant, but the overall number of impacts decrease because the molecules have to travel longer before they hit the wall, and the number of impacts per sq inch also decreases because the internal surface is expanding. This causes the gas pressure to decrease.
• This guy is really good
• Why is the internal energy constant in case of an isothermal condition?
Why is delta-U equal to 0 for the same?
I don't seem to get it physically. I do get it mathematically.
• 'U' for gases is mainly due to kinetic energy of the molecules nd we know that avg KE of a sample of gas purely depends on the temperature of the system . Since the temperature remains constant during an isothermal process , there should be no change in the avg KE of the sample, nd thus internal energy remains constant
• I want to know examples of adiabatic system in daily or some system look like this
Could you tell me?
(1 vote)
• Examples of adiabatic compression: (1) the compression of the air-gas mix in a car engine. (2) The shock wave at the nose of a supersonic aircraft.
Examples of adiabatic expansion: any explosion, from a firecracker to an atomic bomb.
The foregoing examples are adiabatic because they occur so fast that no heat is transferred into or away from the gas itself.
• i can't seem to find what im looking for im looking for isometric just isometric drawings and i can't find it?? Help MEE!
(1 vote)
• - what is a kelvin?