What is the Reversible Process in thermodynamics

Reversible process (thermodynamics)

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An alternative definition of a reversible process is a process that, 

after it has taken place, can be reversed and For articles on other 

forms of reversibility, including reversibility of microscopic dynamics, 

see reversibility (disambiguation). In thermodynamics, a reversible 

process, or reversible cycle if the process is cyclic, is a process that can 

be "reversed" by means ofinfinitesimal changes in some property of the 

system without loss or dissipation of energy.^[1] Due to these infinitesimal

changes, the system is in thermodynamic equilibrium throughout the 

entire process. Since it would take an infinite amount of time for the 

reversible process to finish, perfectly reversible processes are 

impossible. However, if the system undergoing the changes responds 

much faster than the applied change, the deviation from reversibility 

may be negligible. In a reversible cycle, the system and its surroundings 

will be exactly the same after each cycle.

causes no change in either the system or its surroundings. In 

thermodynamic terms, a process "taking place" would refer to its 

transition from its initial state to its final state.

Irreversibility

A process that is not reversible is termed irreversible. In an irreversible 

therefore the system is not at equilibrium throughout the process. At 

the same point in an irreversible cycle, 

process, finite changes are made; 

the system will be in the same state, but the surroundings 

are permanently changed after each cycle.

Reversible adiabatic process: The state on the left can be reached from 

the state on the right as well as vice versa without exchanging heat with 

the environment Boundaries and states

A reversible process changes the state of a system in such a way that the 

entropy of the system and its surroundings is zero. Reversible processes define the boundaries of how efficient 

net change in the combined 

heat engines can be in thermodynamics and engineering: a reversible process is one where no heat is lost from 

the system as "waste", and the machine 

is thus as efficient as it can possibly be (seeCarnot cycle).

In some cases, it is important to distinguish between reversible and 

processes are always quasistatic, but the converse is not always true. 

For example, an infinitesimal 

quasistatic processes. Reversible 

compression of a gas in a cylinder where there exists friction between 

the piston and the cylinder is a 

quasistatic, but not reversible process. Although the system has been driven from its equilibrium state by

only an infinitesimal amount, heat has been irreversibly lost due 

to friction, and cannot be recovered by simply 

moving the 

piston infinitesimally in the opposite direction.

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Engineering archaisms

Historically, the term Tesla principle was used to describe (amongst other 

processes invented by Nikola Tesla. However, this phrase is no longer in 

conventional use. The principle was things) certain reversible that some systems could be reversed and operated in a complementary manner. It was developed during Tesla's research in alternating currentswhere the 

current's magnitude and direction varied cyclically. During a 

demonstration of the Tesla turbine, the disks revolved and machinery 

the engine. If the turbine's operation was reversed, the disks acted as a pump.