Question

What is equilibrium in thermodynamics?¿

Answer 1

Equilibrium in thermodynamics refers to the situation when macroscopic variables describing the thermodynamic state of a system does not depend on time. Equilibrium of a system in mechanics means the net external force and torque on the system are zero. The temperature of a body is related to its average internal energy, not to the kinetic energy of motion of its centre of mass. A bullet fired from a gun is not at a higher temperature because of its high speed.

Answer 2

Thermodynamic equilibrium is an axiomatic concept of thermodynamics. ... In thermodynamic equilibrium there are no net macroscopic flows of matter or of energy, either within a system or between systems. In a system that is in its own state of internal thermodynamic equilibrium, no macroscopic change occurs.

Thanks ...