Question

Prove that ‘A reversible process is never attained in practice. It can only be approached’

Answer 1

If during the direct process the parameter A increases, then during the reverse it should decrease, therefore the derivative A at any point in the direct process is positive, the reverse is negative, i.e. complete reversibility is not achieved.

Only with an infinitely slow process (the derivative is 0) can the process be considered reversible.