Question

Why is the work done in a reversible process maximum?

Answer 1

Definitions

Work : In thermodynamics, work is defined as the energy transferred by a system to its surroundings. A system does not contain work, and work is a process performed by or on a system.

Reversible Process:

1. A thermodynamic process is reversible if it can be reverted so that both the system and its surroundings return to their original states with no other changes occurring. In reality, reversible processes do not exist.
2. Thus, reversible processes can be simply described as idealizations or representations of real processes on which the system or device's boundaries are to be defined.

There are two necessary conditions for a reversible process:

1. There is no dissipative force on the system.
2. The process occurs in an infinitely small time.

Explanation

1. Given the conditions for a reversible process, i.e. the process of work should occur in an infinitely small time leaves no time for heat to be lost to the surroundings.
2. Therefore the work done in a reversible process is maximum as energy lost in the form of heat is minimal.

Hence, the conditions for a reversible process prove that the work done in this process is maximum.