The second law of thermodynamics is governed by two statements.
(i) Kelvin-planck statement :- It states that, it is impossible for a device that operates in a cycle to receive heat from a single reservoir & produce net amount of work.
(ii) Clausis statement :- It states that, it is not possible to construct a device that operates in a cycle & produces no other effect other than transfer of heat from a body at higher temperature to a body at lower temperature.
The second law of thermodynamics also tells that for a feasible process, the efficiency of heat engine is always less than 1.
