21. Angular momentum must be conserved in an isolated system . 22. Suppose a system is thermally and mechanically isolated from the environment ( isolated system ). 23. One may imagine an isolated system , initially not in its own state of internal thermal equilibrium. 24. Only an isolated system has a coordinate-independent mass. 25. The claims have been criticized for ignoring that the second law only applies to isolated systems . 26. Suppose we have an isolated system whose macroscopic state is specified by a number of variables. 27. Overall, in an isolated system , the internal energy is constant and the entropy can never decrease. 28. The picture given in the preceding paragraphs is sufficient for description of a completely isolated system . 29. The second law of thermodynamics describes how the entropy of an isolated system changes in time. 30. In physics, isolated systems must obey conservation laws.
